Information

Which animal species is this?


I have been seeing this animal for the past year and I am wondering: "Which species is this?" It has hair and is orange. It has the black spot at the end, but this seems to be the last part because it walks in the other way (in the direction of the part without the black spot). At the other end is smaller reddish spot. It seems that it has 6 legs, but I am not sure because it turns on the right direction quickly. These legs seems to be concentrated on the first side. Its average speed is around 1 mm/s. Maximum speed is 2 mm/s. It is pretty small, around 4 mm, so I can't see more details. Below is the photo with the millimeter paper.

I placed it in a small paper envelope (2×5cm) for one day and it is still alive. Additional pictures:

Top:

Bottom:

Data about the location:

  • Northern Italy, 100 km from the coast
  • altitude: 700 m
  • room temperature: 21 °C

Which animal species is this? - Biology

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    Sensory Biology Around the Animal Kingdom

    The Scientist Staff
    Sep 1, 2016

    © TIM ROBBERTS/GETTY IMAGES

    Jump to discussions on:

    G rowing up, we learn that there are five senses: sight, smell, touch, taste, and hearing. For the past five years, The Scientist has taken deep dives into each of those senses, explorations that revealed diverse mechanisms of perception and the impressive range of these senses in humans and diverse other animals. But as any biologist knows, there are more than just five senses, and it&rsquos difficult to put a number on how many others there are. Humans&rsquo vestibular sense, for example, detects gravity and balance through special organs in the bony labyrinth of the inner ear. Receptors in our muscles and joints inform our sense of body position. (See &ldquoProprioception: The Sense Within.&rdquo) And around the animal kingdom, numerous other sense organs aid the perception of their worlds.

    Detecting Gravity and Motion

    A BALANCING ACT: Ctenophore statocysts (1), consist.

    The comb jelly’s single statocyst sits at the animal’s uppermost tip, under a transparent dome of fused cilia. A mass of cells called lithocytes, each containing a large, membrane-bound concretion of minerals, forms a statolith, which sits atop four columns called balancers, each made up of 150–200 sensory cilia. As the organism tilts, the statolith falls towards the Earth’s core, bending the balancers. Each balancer is linked to two rows of the ctenophore’s eight comb plates, from which extend hundreds of thousands of cilia that beat together as a unit to propel the animal. As the balancers bend, they adjust the frequency of ciliary beating in their associated comb plates. “They’re the pacemakers for the beating of the locomotor cilia,” says Sidney Tamm, a researcher at the Marine Biological Laboratory in Woods Hole, Massachusetts, who has detailed the structure and function of the ctenophore statocyst (Biol Bull, 227:7-18, 2014 Biol Bull, 229:173-84, 2015).

    Sensing gravity’s pull and the subsequent ciliary response is entirely mechanical, Tamm notes—no nerves are involved in ctenophore statocyst function. Most other animals with statocyst sensing, on the other hand, do employ a nervous system. Statocysts exist in diverse invertebrate species, from flatworms to bivalves to cephalopods. Although the details of the statocyst’s architecture vary greatly across these different groups, it is generally a balloon-shape structure with a statolith in the center and sensory hair cells around the perimeter. As the statolith, which can be cell-based as in the ctenophore or a noncellular mineralized mass, falls against one side of the sac, it triggers those hair cells to initiate a nervous impulse that travels to the brain.

    The complexity of the statocyst system appears to correlate with the complexity of a species’ movement and behavior, says Heike Neumeister, a researcher at the City University of New York. Squids and octopuses, which move rapidly around in three-dimensional space, for example, have highly adapted equilibrium receptor organs. Likewise, the nautilus, whose relatives were among the first animals to leave the bottom of the ocean and begin swimming and employing buoyancy, has a fairly advanced system. Each of its two statocysts is able to detect not only gravity, like the ctenophore’s, but angular accelerations as well, like those of octopuses, squids, and cuttlefishes (Phil Trans R Soc Lond B, 352:1565-88, 1997). “[Nautilus] statocysts are an intermediate state of evolution between simpler mollusks and modern cephalopods,” says Neumeister.

    These sensory systems may be damaged by the man-made noise now resonating throughout the world’s oceans. Michel André, a bioacoustics researcher at the Polytechnic University of Catalonia in Barcelona, Spain, started looking into the effects of noise pollution on cephalopods after the number of giant squid washing ashore along the west coast of Spain shot up in 2001 and then again in 2003. “The postmortem analysis couldn’t reveal the causes of the death,” recalls André. Nearby, however, researchers were conducting ocean seismic surveys, using pulses of high-intensity, low-frequency sound to map the ocean floor. Although, these animals don’t have ears, André and others wondered if that noise might be affecting the squids’ sense of balance.

    Sure enough, exposing squid, octopuses, and cuttlefish to low-frequency sound, which caused the animals’ whole bodies to vibrate, universally resulted in damage to their statocysts. Hair cells were ruptured or missing the statocysts themselves sometimes had lesions or holes even the associated nerve fibers suffered damage. As a result, the animals became disoriented, often floating to the water’s surface (Front Ecol Environ, doi:10.1890/100124, 2011). “They eventually died because they were not eating,” says André. “I don’t think that [anyone thought] that animals who could not hear would be suffering from acoustic trauma. . . . This is something we have to be concerned about.”

    Feeling the Flow

    © CLAUS LUNAU/SCIENCE SOURCE Light, sound, and odors travel through water very differently than they do in air. Accordingly, aquatic animals have sensory systems tuned to their fluid medium—most notably, the lateral line system. Observable as distinct pores that run along the flanks and dot the heads of more than 30,000 fish species, the lateral line is composed of mechanoreceptors called neuromasts—clusters of hair cells not unlike those found in the mammalian ear and vestibular system—that relay information about the velocity and acceleration of water flow.

    “If you live underwater, the water is often moving with respect to your body, and it’s carrying the environment with it,” says University of California, Irvine, biologist Matt McHenry, who studies the lateral line sense in fish. “To have some sense of where it’s going and how fast it’s going seems pretty fundamental. It makes a lot of sense that they would be tuned in to flow.” Despite more than 100 years of research on the lateral line, however, many questions remain about its structure and function, how the sense relays information to the nervous system, and how it affects fish behavior.

    NEUROMASTS: Clusters of hair cells project from the surface of a larval zebrafish’s skin to sense the water’s movement. (Cupula has been removed.) JURGEN BERGER/MAX PLANCK INSTITUTE FOR DEVELOPMENTAL BIOLOGY Transparent zebrafish larvae, whose surface lateral line structures can be observed without the need for dissection, are starting to yield answers. Using a high-power microscope, Jimmy Liao of the University of Florida’s Whitney Laboratory for Marine Science and his colleagues attach tiny glass probes to individual neuromasts and stimulate the mechanoreceptors with controlled vibrations. “We’re able to tickle an individual neuromast and record from the neuron that innervates that specific cluster,” he says. With this system, Liao’s team has found that a neuromast’s response to different water velocities depends on its position in space (J Neurophysiol, 112:1329-39, 2014). “If you bend [a neuromast] halfway and then give it a velocity, that’s very different than just giving it the velocity in its normal configuration,” Liao says.

    Liao and his collaborators have also determined that the sensors stimulate sensory neurons in a nonlinear fashion—that is, with increasing velocity, the nervous response only increases up to a certain point, then levels off (J Neurophysiol, 113:657-68, 2015). And the researchers have traced the nervous connections from neuromasts found on the flank of a fish’s body to specific locations within the posterior lateral line ganglion, a group of nerve cells outside the brain. Tail neuromasts are connected to afferent neurons found in the center of the ganglion, Liao says, while neuromasts closer to the head contact neurons on its periphery.

    When it comes to the specific role of lateral line sensing in fish behavior, however, the research is still somewhat murky. “We have a very crude understanding for what behaviors depend on this sense,” says McHenry. “At a receptor level, I think we have a pretty good handle for what kind of information they’re extracting, but in real-world applications it’s not clear why that’s useful a lot of the time.”

    HAIRLINE: Modified epithelial cells called hair cells—similar to those in the mammalian inner ear—are the work horses of the lateral line in fishes. Hair cells connect to afferent neurons and are grouped together into structures called neuromasts whose hairs are covered by a jelly-like secretion called the cupula. When moving water or vibrations trigger neuromasts, which sit inside pores on the head, body, and tail of the fish, hair cells stimulate neurons to relay information about velocity or acceleration to sensory ganglia distributed through the fish’s body. © LAURIE O'KEEFE One challenge is isolating sensory information detected by the lateral line from information detected by other fish senses, specifically vision, says Sheryl Coombs, an emeritus professor at Bowling Green State University who has spent decades studying the links between the lateral line sense and fish behavior. “Most behaviors rely on animals integrating information across the senses,” she says. “It’s difficult sometimes to pick apart the role of the lateral line because the senses act together in complementary ways, often.”

    To get around this problem, Coombs has studied nocturnal fish and species that live in complete darkness, such as the Mexican blind cave fish (Astyanax mexicanus), which often lacks eyes altogether. In this species, Coombs has found that the fish may use their lateral line sense to construct rudimentary maps of their surroundings. “They’re basically ‘listening’—for lack of a better word—to their own flow field that they create by moving through the water,” she says. “They create the flow, and then they’re listening to distortions in that flow created by the presence of the obstacle. It’s sort of analogous to echolocation in the sense that animals are producing a sound and they’re listening to how the sound bounces back.”

    Magnetoreception

    Mollusks, insects, birds, and some mammals are able to sense Earth’s magnetic field, but how they do so remains a mystery. In the last couple of decades, “most of the research [has focused] on proteins and genetics in the various animals, speculating on possible means of magnetoreception,” says Roswitha Wiltschko, who—along with her husband, Wolfgang Wiltschko—ran a magnetoreception lab at Goethe University Frankfurt, Germany, until she retired in 2012.

    Although the details are still unclear, most magnetoreception researchers have converged upon two key mechanisms: one based on magnetite, an iron oxide found in magnetotactic bacteria, mollusk teeth, and bird beaks and the other on cryptochromes, blue-light photoreceptors first identified in Arabidopsis that are known to mediate a variety of light-related responses in plants and animals.

    Once we have found magnetoreception structures reliably, we can start trying to understand how they convert the magnetic field into a neural response. —Roswitha Winklhofer
    Goethe University Frankfurt

    In 2001, Michael Winklhofer, then at Ludwig Maximilian University of Munich, and colleagues reported their identification of magnetite in the beaks of homing pigeons (Eur J Mineral, 13:659-69). A year earlier, Klaus Schulten of the University of Illinois at Urbana-Champaign and colleagues proposed that cryptochromes in the bird eye might also play a role in avian magnetoreception (A Sense of Mystery,” The Scientist, August 2013.)


    Over the years, support for this idea has emerged. In 2007, Henrik Mouritsen of the University of Oldenburg, Germany, and colleagues showed that blue light–exposed avian cryptochrome 1a indeed forms long-lived radical pairs (PLOS ONE, 2:e1106). And this April, Peter Hore of the University of Oxford and colleagues published a computer-based modeling study showing that light-dependent chemical reactions in cryptochrome proteins in the eyes of migratory birds could “account for the high precision with which birds are able to detect the direction of the Earth’s magnetic field,” the authors wrote (PNAS, 113:4634-39, 2016).

    Birds seem to use both the magnetite and the radical pair/cryptochrome–based mechanisms. Cryptochrome-based orientation has also been reported in Drosophila and cockroaches, and researchers have found evidence of magnetite-based navigation in animals from mollusks to honeybees. And there may be other components of magnetoreception still to discover, as scientists continue their search for magnetic sensory structures across the animal kingdom. Late last year, for example, biophysicist Can Xie of Peking University in Beijing and colleagues identified a Drosophila protein, dubbed MagR, that—when bound to photosensitive Cry—has a permanent magnetic moment, the researchers reported, meaning it spontaneously aligns with magnetic fields (Nat Mater, 15:217-26, 2015). The MagR/Cry complex, the researchers noted, exhibits properties of both magnetite-based and photochemical magnetoreception. (See “Biological Compass,” The Scientist, November 2015). The study was met with skepticism, however, and the results have yet to be independently verified.

    In addition to mechanism, questions remain about the function of magnetoreceptive capabilities. “Once we have found [magnetoreception structures] reliably, we can start trying to understand how they convert the magnetic field into a neural response, and at the brain level, how are the single responses processed and integrated with other navigational information to tell the animal where it is and where to go,” says Winklhofer.

    In the mid-1990s, for example, Wiltschko and her husband Wolfgang demonstrated that migratory birds called silvereyes (Zosterops lateralis) reacted to a strong magnetic pulse by shifting their orientations 90° clockwise, returning to their original headings around a week later (Experientia, 50:697-700, 1994). Magnetic field manipulations can also affect Drosophila navigation, John Phillips, now of Virginia Tech, has shown (J Comp Physiol A, 172:303-08, 1993). And Richard Holland, now of Bangor University, U.K., and colleagues showed in the mid-2000s that experimentally shifting the Earth’s magnetic field altered homing behavior in Eptesicus fuscus bats (Nature, 444:702, 2006).

    “Some animals use their magnetic sense for long-distance navigation, some for magnetic alignment or orientation, and some animals may have the capability to sense the magnetic field but do nothing,” says Xie. Or, at least, nothing that has yet been recognized by researchers.

    —Tracy Vence

    Thermoreception

    HEAT SENSE: Pit organs consist of a large, hollow, air-filled outer chamber and a smaller inner chamber separated by a membrane embedded with heat-sensitive receptors. The receptors are innervated by the trigeminal ganglia (TG), which transmit the infrared signals to the brain. © LAURIE O'KEEFE Many animals are able to sense heat in the environment, but vampire bats and several types of snakes are the only vertebrates known to have highly specialized systems for doing so. Humans and other mammals sense external temperature with heat-sensitive nerve fibers, but pit vipers, boa constrictors, and pythons have evolved organs in their faces that the animals use to detect infrared (IR) energy emitted by prey and to select ecological niches. And vampire bats have IR receptors on their noses that let them home in on the most blood-laden veins in their prey.

    “Infrared sense is basically a souped-up [version] of thermoreception in humans,” says David Julius, a professor and chair of the physiology department at the University of California, San Francisco (UCSF), who studies this sense in snakes. The difference is, snakes and vampire bats “have a very specialized anatomical apparatus to measure heat,” he says.

    These IR-sensing apparatuses, known as pit organs, have evolved at least twice in the snake world—once in the ancient family that includes pythons and boas (family Boidae) and once in the pit vipers (subfamily Crotalinae), which includes rattlesnakes. Pythons and boas have three or more simple pits between scales on their upper and sometimes lower lips each pit consists of a membrane that is lined with heat-sensitive receptors innervated by the trigeminal nerve. Pit vipers, by contrast, typically have one large, deep pit on either side of their heads, and the structure is more complex, lined with a richly vascularized membrane covering an air-filled chamber that directs heat onto the IR-sensitive tissue. This geometry maximizes heat absorption, Julius notes, and also ensures efficient cooling of the pit, which reduces thermal afterimages.

    In 2010, Julius and Elena Gracheva, now at Yale University, identified the heat-sensitive ion channel TRPA1 (transient receptor potential cation channel A1) that triggers the trigeminal nerve signal in both groups of snakes (Nature, 464:1006-11). The same channels in humans are activated by chemical irritants such as mustard oil or by acid, and the resulting signal is similar to those produced by wounds on the skin, Gracheva says. In snakes, these channels have mutated to become sensitive to heat as well.

    Vampire bats—which, true to their name, feed on the blood of other creatures—are the only mammals known to have a highly developed infrared sense. Like snakes, the bats have an innervated epithelial pit, which is located in a membrane on the bats’ noses. In 2011, Julius, Gracheva, and their colleagues identified the key heat-sensitive ion channel in vampire bats as TRPV1 (Nature, 476:88-91). In humans, this channel is normally triggered by temperatures above 43 °C, but in the bats, it is activated at 30 °C, the researchers found.

    More than 30 years ago biologists Peter Hartline, now of New England Biolabs in Ipswich, Massachusetts, and Eric Newman, now at the University of Minnesota, found that information from the snake pit organ activates a brain region called the optic tectum (known in mammals as the superior colliculus), which is known to process visual input (Science, 213:789-91, 1981). The pit organ appears to act like a pinhole camera for infrared light, producing an IR image, Newman says. However, it’s impossible to know whether snakes actually “see” in infrared.

    “Unfortunately we don’t have a sensory map [of the brain] in snakes or vampire bats,” Gracheva agrees. “I don’t think we have enough data to say [these animals] can superimpose a sensory picture onto the visual picture, though it definitely would make sense.”

    —Tanya Lewis

    Electroreception

    Apullae of Lorenzini openings in great white shark skin © GARY BELL/OCEANWIDEIMAGES Sharks and other fish are well known for their ability to detect electric fields, with some species able to sense fields as weak as a few nanovolts per centimeter—several million times more sensitive than humans. But it turns out that they aren’t the only ones. In recent years, evidence for electroreception has been accumulating all over the animal kingdom: in monotremes (such as the platypus), crayfish, dolphins, and, most recently, bees.

    “The number of taxa that are now effectively known to detect weak electric fields is increasing,” says Shaun Collin of the University of Western Australia, “although some of these we don’t know very much about yet, and for some we only have evidence of a behavioral response.”

    ELECTRIC SLIDE: Sharks and other cartilaginous fish have highly specialized electroreceptive organs called the ampullae of Lorenzini. These bundles of sensory cells, situated at the end of jelly-filled pores in the skin, detect electric fields in the water surrounding the fish and send signals to the brain. © LAURIE O'KEEFE First formally described in the middle of the last century in weakly electric fish (J Exp Biol, 35:451-86, 1958), electroreception operates most effectively over less than half a meter in water—a more conductive medium than air. The sense is most frequently employed by aquatic or semi-aquatic animals to find prey in environments where other senses are less reliable—in murky or turbid water, for example, or where food can bury itself in sediment. Such “electrolocation” is usually passive, relying on bioelectric fields generated by the nerves and muscles of other animals, but some species, such as knifefish, measure distortions in electric fields that they themselves generate.

    Researchers have also documented other functions of electroreception. “Especially in the stingray family, it is used in social communication,” says Collin. “The opposite sex can use it to assess whether there’s a potential for mating, and discriminate that opportunity from something that could turn into predation.” And some baby sharks appear to use electroreception for predator aversion. According to research by Collin’s group, electric fields trigger a “freeze” response in bamboo sharks while they’re still in egg sacs (PLOS ONE, doi:10.1371/journal.pone.0052551, 2013).

    Electroreception is thought to be an ancestral trait among vertebrates that has subsequently been lost from several lineages (including the amniotes—the group comprising reptiles, birds, and mammals), and then re-evolved independently at least twice in teleost fish and once in monotremes. In 2011, researchers added cetaceans to that list, after discovering electroreception in the Guiana dolphin, a resident of murky coastal waters around South America that evolved its electroreceptors from what used to be whiskers (Proc R Soc B, doi:10.1098/rspb.2011.1127).

    Most electroreceptors consist of modified hair cells with voltage-sensitive protein channels, arranged in bundles that activate nerves leading to the brain. “The classic example is the ampullae of Lorenzini,” says Collin. Described in 1678 by Italian anatomist Stefano Lorenzini, ampullae are extensions of the lateral line system that are present in dense clusters over the heads of cartilaginous fish such as sharks and rays. Each ampulla consists of a bundle of electrosensory cells at the end of a pore filled with a hydrogel that was recently shown to have the highest reported proton conductivity of any known biological material (Sci Advances, 2:e1600112, 2016).

    But pinning down how any of these receptors operate at a molecular level remains a challenge, notes Clare Baker, a neuroscientist at the University of Cambridge. “We hardly know anything about the specific genes involved, or the genetic basis for building electroreceptors in the embryo,” she says, adding that the major animal models in fish and amphibians—zebrafish Danio rerio and frog genus Xenopus—both belong to lineages that have lost electroreception altogether.

    Baker’s group has adopted the paddlefish, a relative of the sturgeon, as a model organism. Electrosensitivity in these animals, as in other primitive vertebrates such as the axolotl, depends on modified hair cells that develop as part of the ancestral lateral line system and are homologous to the ampullary organs of sharks. Fate-mapping experiments in these species have identified candidate genes for electroreceptor development (Evol Dev, 14:277-85, 2012), and Baker says future work will use gene-editing technologies such as CRISPR-Cas9 to get a better grip on these genes’ functions.

    Meanwhile, the field is continuing to uncover surprises. In 2013, research from Daniel Robert’s group at the University of Bristol showed that bumblebees are capable of detecting the weak electric fields generated by flowers, and use this information to discriminate between food sources of differing quality (Science, 340:66-69). And earlier this year, the same researchers identified bees’ electrosensors as tiny hairs that move in the presence of electric fields (PNAS, 113:7261-65, 2016). “Electroreception provides another source of information,” says Robert, who suspects that a flower’s electric field may indicate to bees when nectar and pollen are available. “They’re really good at learning where the resources are.”

    For Collin, the Bristol team’s findings are indicative of how much more there is still to discover about electroreception. Even in large clades such as reptiles and birds, “there is circumstantial evidence that they might have electroreception, but there hasn’t been anything concrete,” he says. “There may well still be examples of functions we don’t even know about.”


    Animal Biology

    Take what you learn in What Is an Animal? and put it to the test in Animal Biology. Think about how animals are related. How does a bighorn sheep use its horns, compared to an elk and its antlers? As you walk through a herd of large mammals and examine a flock of bird specimens, learn about variation and domestication.

    Through specimens, models, and games, this journey through the animal kingdom showcases the vibrant diversity of life on Earth.


    Trumpeter swan

    People living in 19th-century Minnesota must have found trumpeter swans delicious, because the species was eliminated from the state — and practically from its entire range in the United States — after it was over-harvested for food. The largest native waterfowl species in North America, trumpeter swans didn't successfully return to the wild in Minnesota until a number of ecological agencies partnered in the 1980s to restore them, according to a statement released Feb. 11, 2016, by the Minnesota Department of Natural Resources (MDNR). Trumpeter swans' Minnesota population is currently estimated at 17,000, and continues to grow, the MDNR reported.


    Classification of Animals

    There is a large number of animals in the world, so many that it is impossible to list them all. However, there are a few methods to classify them. This article provides some means to do the same.

    There is a large number of animals in the world, so many that it is impossible to list them all. However, there are a few methods to classify them. This article provides some means to do the same.

    Animals are multicellular i.e. organisms with multiple cells which grow to take a particular shape. Usually, all animals, whether wild or pets, can move independently and without any support. They consume other living organisms for food. They get their name from the Latin term animal, which means soul. In biological terms, the word animal means all categories which belong to the Kingdom Animalia, which includes creatures which range from humans to insects.

    Animal Classification

    Would you like to write for us? Well, we're looking for good writers who want to spread the word. Get in touch with us and we'll talk.

    Classifying animals basically means dividing them into two main groups – vertebrates and invertebrates. Vertebrates have a backbone, while invertebrates are those which don’t. In all, there are more than 800,000 animal species in the Kingdom Animalia and most of them are included in the phylum of Arthropod i.e. invertebrates. Usually, people don’t think of earthworms or jellyfish as animals, but actually they are, thereby making the animal kingdom classification extremely huge. Each living organism is classified into Kingdom – Phylum – Class – Order – Family – Genus – Species. There are basically five kingdoms. They are listed in the following table.

    Kingdom Inclusions
    Animalia Animals
    Plantae Plants
    Protista Single-celled organisms
    Fungi Yeast, molds, mushrooms, etc.
    Monera Bacteria

    The next classification is the phylum or phyla. There are different phyla in each kingdom. Chordata is the most well-known phyla, as it includes all animals which has a backbone, which includes all birds, fish, mammals, amphibians, insects, snails, etc. Some other names of phyla are listed below.

    Phyla Description
    Echinodermata Starfish (marine)
    Ctenophora Comb Jellies
    Porifera Sponge
    Cnidaria Jellyfish
    Arthropoda Insects
    Nematodes Parasitic worms
    Annelida Worms
    Platyhelminthes Flatworms
    Bryozoa Moss animals

    After phyla comes the class. The class of the animal kingdom is broken down into the following groups.

    The following table is a brief example of how the class is further divided into order, family, and genus. Since the classification is very vast, only a few examples have been taken to show the representation.

    • Chiroptera (bats)
    • Carnivora (cats, dogs)
    • Proboscidea (elephants)
    • Rodentia(Rodents)
    • Primates
    • Panthera (lion, tiger)
      1. Leo (the lion)
      2. Tigris (tigers)
    • Felis (domestic cats)
    • Neofelis (clouded leopard)

    Hylobitadae Family (gibbons)

    Classification of Animals for Kids

    When you teach kids of how to classify animals, it may not be possible to explain it all in one go. So while explaining, you can use the bottom up instead of the top down approach, starting from the species and ending with the Kingdom. For example, you can ask them to list the common trait between cats, dogs, dolphins, whales, and humans. The answer to that is milk. All these animals feed their young milk when they are born. Moreover, they have hair on their body and are warm-blooded, meaning they can adapt to different rage of temperatures. You can use similar examples while teaching kids.

    Charting a Classification

    Would you like to write for us? Well, we're looking for good writers who want to spread the word. Get in touch with us and we'll talk.

    Making a chart of animal kingdom is not as tough as it may seem. The only thing you should know are the different classifications and then prepare a chart. While making a chart, you can break the animal kingdom into two parts, vertebrates (those which have bones) and invertebrates (those which don’t have bones). Once you have done that, you can classify them into sub categories like mammals, birds, amphibians, fish, and reptiles for vertebrates and list the common characteristics of these categories. Invertebrates include porifera (like sponge), starfish, mollusks, arthropods, etc. You can further divide animals with backbones into cold-blooded reptiles like snakes, frogs, etc., warm-blooded animals like whales, dolphins, etc., winged animals like birds, animals which have gills such as fish, and those that have lungs as well as gills, like frogs.

    Classifying animals is quite easy, but you need to know which category they fall into. While teaching kids, it’s always better to use pictorial forms so that they can learn better.

    Related Posts

    Sexual and asexual reproduction are the two means of producing offspring. Read this article to gain more information about asexual reproduction in the animal kingdom.

    Are you searching for some interesting facts regarding classification of the algal species called volvox? The following article will surely help you in this matter.

    How is cytokinesis in plant and animal cells different from each other? Read on to know the answers to this question and more.


    Resource Links

    Amphibian Project
    A collaboration of five conservation professionals, the Emerging Wildlife Conservation Leader&rsquos program and Amphibian Ark to raise funds for and awareness of the global amphibian extinction crisis. Downloadable classroom curricula, field projects, hands on activities and more.

    Monarch Watch
    An outreach program from the Kansas Biological Survey, University of Kansas, that gets children of all ages involved in science. Learn about migration, life cycle, rearing, tagging, in-class research projects, Blog and forum resources and other links.

    Operation Rubythroat: The Hummingbird Project
    A project from the Hilton Pond Center for Piedmont Natural History, participants in the US, Canada, Mexico, and Central America collaborate to study behavior and distribution of the Ruby-throated Hummingbird. Free AV teleconferences are available to teachers & students.

    Project Pigeon Watch
    A project from the Cornell Lab of Ornithology to learn about city pigeons, watch pigeons for science, learn cool facts, and increase awareness of nature in your neighborhood. Downloadable Pigeon Watch kits with posters, guides data sheets and more.

    Urban Bird Studies
    A project from the Cornell Lab of Ornithology, the Celebrate Urban Bird outreach is presented in English or Spanish. Receive a free Celebrate Urban Bird&rsquos kit, information about over 650 Mini Grants or a 10 Minutes bird observation project. This is an opportunity to get &ldquooutside.&rdquo

    Animals in Research

    Animals in Research: Questions and Answers
    The American Physiological Society (The APS) provides answers to FAQ&rsquos about animals in research. Developed for secondary school biology teachers to use in classroom discussions or for students to use in research papers or debates there are multiple links to government resources.

    Kids4Research
    The American Association for Laboratory Animal Science (AALAS) site that provides information to students, teachers and parents on responsible lab animal care and use in biomedical research testing and education.

    Animal Diversity

    Animal Diversity Web (ADW)
    University of Michigan&rsquos Museum of Zoology site that provides a searchable encyclopedia of animal natural history, distribution, classification and conservation biology facilitating inquiry driven learning where students can learn the biology of species and share their work worldwide.

    ARKive Images of Life on Earth
    A not-for-profit Wildscreen initiative, whose mission is to promote public understanding, appreciation and conservation of biodiversity. A unique collection of multimedia and fact-files that houses free educational resources, online guides and Google Earth access.

    Carnivore Ecology & Conservation
    This is the personal home page of Guillaume Chapron. His site provides current and rigorous information to carnivore conservationists, scientists and concerned citizens in the form of headlines, papers, theses, resources and knowledge in Ecology, Zoology, Conservation and more.

    Animal Keys and Field Guides

    Anatomical Atlas of Flies
    CSIRO built this site to accompany an identification key to fly families of Australia and the US NSF-funded research into the evolutionary history of flies. This standalone resource uses high-resolution digital imaging for four major fly groups. Click on the CSIRO link to go to Australia&rsquos national science agency.

    Field Guides
    eNature,com provides comprehensive searches of Wildlife Guides to more than 5,500 species in North America. Birding guides, sky guides, articles, mammal tracks, zip guides, endangered species, gardening, wildlife lists, Ask an Expert and even send eCards.

    North American Mammals
    The Smithsonian Institution presents ways to search for mammals. Use a Map Search of North America, a Search by Species Name, or Family Tree, or Conservation Status or Special Collections using skulls, bone and teeth images. Download lesson plans and Map Tutor for using Google Earth.

    Animal Specifics

    Birds

    All About Birds
    Cornell Lab of Ornithology site that provides basics for first timers, online guides for bird identification, gear guide, attracting birds, conservation and additional resources on bird sounds, video, news, events and eBirds that permits tracking and reporting of birds.

    Invertebrates

    Center for Insect Science
    The University of Arizona site that provides lessons on the use of live insects as teaching models for elementary use called Using Live Insects in Elementary Classrooms for Early Lessons in Life and for Grades 9-12 called Acres of Insects.

    WormAtlas
    A database of behavioral and structural anatomy of Caenorhabditis elegans (C.elegans) that includes information on worm anatomy, fine structure, individual neurons, cell identification, glossary, lineage tree, and other news, notes, images, and a worm community forum.

    Primates

    Jane Goodall Institute&rsquos Center for Primate Studies
    The University of Minnesota&rsquos, Center for Primate Studies permits discovery of chimpanzees. Access information, videos, sounds of chimps and those who research their behavior. Tour Gombe or download activities to use in the classroom with additional links to resources.

    Animal Videos

    Watch NOVA Online- Nature
    View video clips or a selection on entire NOVA programs online. Teachers resources including classroom tools, activities, TV program descriptions, and interactives for students are also available.


    Science News

    Science News was founded in 1921 as an independent, nonprofit source of accurate information on the latest news of science, medicine and technology. Today, our mission remains the same: to empower people to evaluate the news and the world around them. It is published by the Society for Science, a nonprofit 501(c)(3) membership organization dedicated to public engagement in scientific research and education.

    © Society for Science & the Public 2000–2021. All rights reserved.


    List of Sea Animals A-Z

    The ocean, the original home of earth’s animal life, has creatures of every size and type. It’s an exciting place to explore. Read through this list of sea animals𠅊rranged in alphabetical order—to start exploring what&aposs in our seas. See photos, pictures, and facts. Start your journey now and see for yourself how awesome our sea really is!

      : a large edible sea snail of coastal waters : a prized species of tuna : a small, oily fish of the Atlantic and Pacific, providing food for many fish, marine mammals, and birds : a bright-colored fish of coral reefs

    An abalone pried from the rocks

      : an arthropod of coastal waters that attaches itself to rocks and shells : a tropical and subtropical predatory fish with a feisty appearance : a delicacy on the eastern coast of the US : the world’s largest marine animal : an aggressive shark that can thrive in both salt water and fresh water

      : a coral-inhabiting fish that removes parasites from other fish : a small tropical fish of the Indian and Pacific Oceans, with orange and white stripes : a deep-sea fish, formerly a staple food in Europe and America, now greatly reduced in numbers in the Atlantic : an edible shellfish with a distinctive spiral shell : polyps, mostly tropical, mostly living in huge colonies along with photosynthesizing microorganisms : a large sea star that feeds on corals : a squid-like creature belonging to the mollusk family

    Triggerfish being cleaned by wrasses (small blue fish), Red Sea

      an intelligent, vocal, social sea mammal a brightly colored fish of coral reefs : a showy tropical fish of the Indian and Pacific Oceans, with dragon-like eyes and fins : perch-like fish of tropical and subtropical waters, often associated with jellyfish or sargasso weed or Sea Cow: a herbivorous marine mammal, a threatened species of the coastal Indian Ocean : a large, prized edible crab from the western coast of North America

      : long-bodied fishes mostly living in shallow waters : a large seal, with big-nosed males, living in the waters around western North America and Antarctica : a bright-colored shrimp of the Indo-Pacific region that lives cooperatively on other sea animals : the world’s largest living reptile, found in Southeast Asian and Australian estuaries

    75 Animal Facts That Will Change the Way You View the Animal Kingdom

    Impress your friends with mind-blowing trivia about dolphins, koalas, bats, and more.

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    With an estimated 7.77 million species of animals on the planet, the animal kingdom is an undeniably diverse place. But while the breadth of earthly biodiversity may be well known, the incredible things our animal counterparts can do are often hidden to humans. From furry creatures you never realized kissed to those who enjoy getting tipsy, these amazing animal facts are sure to wow even the biggest animal lovers out there.

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    Koalas might not seem to have a lot in common with us, but if you were to take a closer look at their hands, you'd see that they have fingerprints that are just like humans'. In fact, they're so similar when it comes to the distinctive loops and arches, that in Australia, "police feared that criminal investigations may have been hampered by koala prints," according to Ripley's Believe It or Not. Any koalas who want to commit crimes would be wise to do so wearing gloves.

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    Parrots may be associated with pirates, but it turns out African grey parrots are nothing like the infamously greedy, treasure-seeking criminals. Instead, researchers have discovered that the colorful birds will "voluntarily help each other obtain food rewards" and perform "selfless" acts, according to a 2020 study published in Current Biology. Study co-author Auguste von Bayern noted, "African grey parrots were intrinsically motivated to help others, even if the other individual was not their friend, so they behaved very 'prosocially.'"

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    Prairie dogs are quirky creatures for a number of reasons: They're giant rodents, they dig massive interconnected underground homes, and they kiss. While they're actually touching their front teeth in order to identify each other when they seem to be sweetly sharing a smooch, the BBC explains that scientists believe prairie dogs "'kiss and cuddle' more when they are being watched by zoo visitors," because they "appeared to enjoy the attention."

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    Crabs may be able to intimidate other creatures with their claws, but if that's not enough, ghost crabs will growl at their enemies like a dog. However, unlike our canine friends, crabs make these fearsome noises using teeth located in their stomachs. "There are three main teeth—a medial tooth and two lateral teeth—that are essentially elongated, hard (calcified) structures. They are part of the gastric mill apparatus in the stomach, where they rub against each other to grind up food," Jennifer Taylor, from the University of California, San Diego, told Newsweek. She and her colleagues were able to nail down the source of the noise after noticing that "the crabs [were] 'growling' at" them.

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    You might think that boxers have the most impressive jabs, hooks, and uppercuts on the planet, but it's the mantis shrimp that boasts the world's fastest punch. Traveling at about 50 mph, when a shrimp punches, its little fist of fury (which, of course, isn't a fist at all) is "accelerating faster than a .22-caliber bullet," according to Science. National Geographic shared the tale of one such small smasher, explaining that "in April 1998, an aggressive creature named Tyson smashed through the quarter-inch-thick glass wall of his cell. He was soon subdued by nervous attendants and moved to a more secure facility in Great Yarmouth. Unlike his heavyweight namesake [former professional boxer Mike Tyson], Tyson was only four inches long. But scientists have recently found that Tyson, like all his kin, can throw one of the fastest and most powerful punches in nature."

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    While male lions attract their fair share of attention thanks to their impressive manes, it's the female lions who do the bulk of the work when it comes to feeding their families. "Lionesses, not male lions, do the majority of hunting for their pride," according to CBS News. "Lionesses hunt around 90 percent of the time, while the males protect their pride."

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    Narwhals are unlike most other whales because they have what appears to be a giant tusk. But that's not actually a tusk at all—what you're seeing is a tooth. Harvard University's Martin Nweeia told the BBC that the "tooth is almost like a piece of skin in the sense that it has all these sensory nerve endings," adding that it's "essentially built inside out."

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    Dogs are well known for being man's best friend, and it turns out that's a relationship that goes back longer than you might expect. According to Guinness World Records, the oldest known breed of domesticated dog goes all the way back to 329 BC. "Saluki dogs were revered in ancient Egypt, being kept as royal pets and being mummified after death," they note. "There are carvings found in Sumer (present-day southern Iraq) which represent a dog, closely resembling a saluki, which date back to 7000 BC."

    Cats have also been hanging around humans for thousands of years. Guinness World Records reports that we've been domesticating cats for 9,500 years. Proof of this came in 2004 when the "bones of a cat were discovered in the neolithic village of Shillourokambos on Cyprus. The position of the cat in the ground was next to the bones of a human, whose similar state of preservation strongly suggests they were buried together."

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    Puffins surely have enough to be proud of with their beautiful beaks, but the seabirds also happen to be quite clever. According to a 2019 study published in Proceedings of the National Academy of Sciences (PNAS), Atlantic puffins in both Wales and Iceland were observed "spontaneously using a small wooden stick to scratch their bodies." Indeed, in a video shared by Science, a little puffin can be seen picking up a tiny twig before using it to scratch an itchy spot on its belly.

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    "Most humans (say 70 percent to 95 percent) are right-handed, a minority (say 5 percent to 30 percent) are left-handed," according to Scientific American. And the same holds true for bottlenose dolphins. In fact, the savvy swimmers are even more right-handed than we are. A team led by Florida's Dolphin Communication Project took a look at the feeding behavior of bottlenose dolphins and found that the animals were turning to their left side 99.44 percent of the time, which "actually suggests a right-side bias," according to IFL Science. "It places the dolphin's right side and right eye close to the ocean floor as it hunts."

    If you're ever in the area of "the Broadway medians at 63rd and 76th streets" in New York City, keep an eye on the ground for crawling critters and you might spot something rare. That's where the "ManhattAnt" can be found, an ant that only lives in the one small area of the city. "It's a relative of the cornfield ant, and it looks like it's from Europe, but we can't match it up with any of the European species," Rob Dunn, a biology professor at North Carolina State University, told the New York Post. Dunn and his team discovered the isolated ant variety in 2012.

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    Cows have to deal with pesky flies that are beyond annoying for the docile creatures. Luckily, farmers can now protect their animals by painting them with zebra-like stripes. According to a 2019 study published in PLOS One, "the numbers of biting flies on Japanese Black cows painted with black-and-white stripes were significantly lower than those on non-painted cows and cows painted only with black stripes." IFL Science suggests this might work because "the stripes may cause a kind of motion camouflage targeted at the insects' vision, confusing them much in the way that optical illusions … confuse us."

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    Monkeys are undeniably cute. They can also be pretty darn gross. Capuchin monkeys, for example, urinate on their hands and feet when they're feeling "randy." "We think the alpha males might use urine-washing to convey warm, fuzzy feelings to females, that their solicitation is working and that there's no need to run away," primatologist Kimran Miller told NBC News. "Or they could be doing it because they're excited." Either way, ew!

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    People who come from different areas around the world tend to speak with inflections, fluctuations, and patterns that are specific to their home regions. Apparently, the same can be said for whales. Researchers from Dalhousie University in Canada and the University of St. Andrews in the UK have found evidence that seems to show whales in the Caribbean have a different "accent" than whales in other oceans.

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    In Nanning, the capital of China's Guangxi province, a man named Pang Cong has a rather remarkable animal living on his farm: a 1,102-pound pig. That's roughly the same size as a full-grown adult male polar bear. According to Bloomberg, massive swine of that size "can sell for more than 10,000 yuan ($1,399), over three times higher than the average monthly disposable income" in the area.

    National Geographic via YouTube

    Sharks boast some enviable—and terrifying—features, like their sleek design and razor-sharp teeth. And while glow-in-the-dark sharks sound like something you'd see in a sci-fi film, they're totally real, as noted in a 2019 study published in iScience. Researchers were already aware that some shark species produce a glow that only other sharks can see, but now scientists have discovered that "previously unknown small-molecule metabolites are the cause of the green glow," according to CNN. This glow "helps sharks identify each other and even fight against infection on a microbial level."

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    While it's not a secret that snails have shells, you probably didn't know that some actually have hairy shells. These hairs are rather handy to have, as they help a snail stick to wet surfaces like leaves.

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    Cowbirds lay their eggs in other bird species' nests, which means that the little ones eventually need to reconnect with their own kind when the time is right. And when that time comes, the young birds have a trick for figuring out who to reach out to. "Juvenile cowbirds readily recognize and affiliate with other cowbirds. That's because they have a secret handshake or password," according to Science Daily. To put it more simply, they use "a specific chatter call" to beckon each other.

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    If you have best friends who have been around since you were a child, then you have something in common with Tasmanian devils. Research has shown that Tasmanian devils form bonds when they're young that last for the rest of their lives. As Zoos Victoria's Marissa Parrott told IFL Science, "In the wild, when baby devils leave their mums, we believe they all socialize together." As the website notes, "young devils have their own dens," "engage in friendly sleep-overs," and when given the chance, they prefer "to share with their … original friends."

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    Those who find themselves in the presence of a grizzly bear will surely want to stay out of reach of this animal's super sharp claws. But they'll certainly also want to keep out of the grizzly's mouth, because these creatures "have a bite-force of over 8,000,000 pascals," according to National Geographic. That means grizzly bears can literally crush a bowling ball between their jaws. Yikes!

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    You might think that a whale's massive size is the only edge they'd need when it comes to hunting in the open waters. But humpback whales actually team up to use a "bubble-net" technique in order to catch their prey. "Sometimes, the whales will swim in an upward spiral and blow bubbles underwater, creating a circular 'net' of bubbles that makes it harder for fish to escape," Science News reports.

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    When you hear a housefly buzzing around your home, you might be annoyed by the persistent sound. However, the next time it happens, try to soothe yourself by noting that the airborne pest is actually buzzing in an F key. How melodious!

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    If you already thought that eels were kind of creepy, then this fact isn't going to make you feel any better about them. Moray eels have what's called pharyngeal jaws, which are a second pair of "Alien-style" jaws that are located in the throat and emerge to grasp prey before pulling the unfortunate meal down into the eel's gullet.

    Over in New Zealand, surfers have noticed the same thing that those who ride the waves in California have witnessed: ducks can surf. The birds do so in order to catch food or simply to move through the water quickly. Sports reporter Francis Malley spotted a female duck and her babies catching a wave and told the New Zealand Herald, "The mother was surfing on her belly on the whitewash. I've never surfed with ducks before so this was a first."

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    They may be cute, but their bite can kill. According to Popular Science, these adorable animals secrete toxins from a gland in the crook of their inner arms. Their bites have caused anaphylactic shock and even death in humans. Better watch out!

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    You might think of pigeons as… not that smart. But it turns out, they're actually quite intelligent. In fact, one 2011 study published in the journal Science found that the birds are capable of doing math at the same level as monkeys. During the study, the pigeons were asked to compare nine images, each containing a different number of objects. The researchers found that the birds were able to rank the images in order of how many objects they contained. Put simply, they learned that the birds could count!

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    Cows may benefit from artificial stripes, but zebras have the real deal. One 2012 report published in the Journal of Experimental Biology suggests that zebras' black and white stripes may be an evolutionary feature to fend off harmful horsefly bites. "A zebra-striped horse model attracts far fewer horseflies than either homogeneous black, brown, grey or white equivalents," the researchers wrote.

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    Humans aren't the only animals who enjoy a drink or two. A 2015 study published in the journal Royal Society Open Science reveals that chimpanzees in Guinea had a fondness for imbibing fermented palm sap and getting tipsy in the process.

    Jiri Prochazka / Shutterstock

    While many scientists believe that tool use among dolphins is a relatively new phenomenon, a 2017 study published in Biology Letters suggests that otters may have been using tools for millions of years. Sea otters frequently use rocks to break open well-armored prey, such as snails.

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    Why tolerate the cold when you could just freeze yourself solid? According to Kenneth Storey, a professor at Carleton University in Ottawa, frogs undergo repeated freeze-thaw cycles. "We have false springs here all the time where it gets really warm and all the snow melts and then suddenly—bam—the wind comes from the north and it's back down to minus 10, minus 15 [Celsius], and they're fine," Storey told National Geographic.

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    Male horses have 40 to 42 permanent teeth, while females have just 36 to 40. According to the VCA Animal Hospital, the original purpose of these extra teeth was as fighting weaponry.

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    If you thought your cat was sleepy, just wait until you hear about koalas. According to the Australian Koala Foundation, these cuties sleep between 18 and 22 hours a day. The koalas' diets require a lot of energy to digest, which is why they've got to nap so much.

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    No, it's not because they're so professional—it's a modernized form of "busyness," the word originally used to describe a group of these weasel-related mammals.

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    And yes, they are called arms, not tentacles. According to the Library of Congress, the animals can taste and grab with the suckers on their arms. Even more impressive? Octopuses are capable of moving at speeds of up to 25 miles per hour.

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    You already know that dolphins are smart. But did you know that they even have their own names? One 2013 study published in PNAS found that bottlenose dolphins develop specific whistles for one another.

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    Reindeers have beautiful baby blues—but only in the winter! According to the Biotechnology and Biological Sciences Research Council, "the eyes of Arctic reindeer change color through the seasons from gold to blue, adapting to extreme changes of light levels in their environment." The change in color impacts how light is reflected through the animals' retina, and improves their vision.

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    Scientists believe that it's so they don't get sunburns while they eat. The animals' tongues are also around 20 inches long.

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    In busy waters, manatees will nudge alligators to get in front, and alligators generally oblige.

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    Everything about life is slow for these sleepy mammals. Most sloths will only have a bowel movement once a week, and it can take them up to 30 days to completely digest a single leaf. For comparison, it takes the average human 12 to 48 hours to ingest, digest, and eliminate waste from food.

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    You probably know that cats love to talk to their humans. But did you know you're unlikely to see your feline friend interact the same way with another cat? That's because other than kittens meowing at their mothers, cats don't meow at other cats.

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    Elephant calves will suck their trunks to comfort themselves. The babies do it for the same reason humans do (it mimics the action of suckling their mothers).

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    According to Bat Conservation International, bats give birth to babies—known as pups—that can weigh as much as one-third of the mother's weight. If that doesn't sound like a lot, imagine a person giving birth to a baby that weighed 40 pounds.

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    Not all creatures head to warmer climates when it gets cold out, and that means they need to learn to survive in chilly conditions. Painted turtles need to adapt to frozen ponds, which restrict their access to the air above the water. They do that by breathing through their butts—specifically, the all-purpose orifice called the cloaca. Thanks to a process called cloacal respiration, the turtles are able to get oxygen directly from the water around them.

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    While you may think that Fido has the same dinnertime experience as you do, he's actually got a much different taste bud arrangement. Humans have about 9,000 taste buds, while dogs have only around 1,700. And while they can identify the same four taste sensations as people, dogs are not fond of salt.

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    They're thought to have up to one million hairs per square inch. Their fur consists of two layers and is designed to trap a layer of air next to their skin so their skin doesn't get wet.

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    According to a 2018 study published in Copeia, alligators often haven't hit their full size until 33.

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    Their legislative powers, however, are still up for debate.

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    Snow leopards have less-developed vocal cords than their fellow large cats, meaning that they can't roar, but make a purr-like sound called a chuff instead. For a 2010 study published in the Biological Journal of the Linnean Society, scientists researched why some cats have a higher-pitched meow than others. They found that it's not size that determines a kitty's call, but habitat.

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    The salamanders are the only vertebrates that can replace their skin, limbs, tail, jaws, and spines at any age. On the flip side, humans can regenerate lost limb buds as embryos and fingertips as young children.

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