This allows them to chew their food into small pieces before swallowing it. Subsequently, they can eat any size plant or animal. Many reptiles must swallow their prey whole, which limits them to hunting smaller game. Like birds, mammals are endothermic , or warm blooded.
They are able to maintain a relatively constant body temperature regardless of external environmental conditions mainly by using internal physiological mechanisms. In other words , they are homeothermic , or stable in core body temperature, as a result of endothermy.
All of the living species of insects, fish, reptiles, and amphibians are ectothermic , or cold blooded. They keep their body temperature in a normal range mainly by avoiding exposure to environmental temperature extremes. For instance, reptiles usually remain in shaded areas on hot days to prevent fatal overheating.
On cold nights, their lowered body temperature can cause them to become sluggish and inactive. In contrast, endothermic animals are able to remain active at night and often in the winter when the air temperatures are especially cold. They can also move about in the heat of very warm days. This ability most likely provided an advantage for the early small mammals in surviving alongside dinosaurs and other large reptiles , which apparently were mostly ectothermic.
The downside of endothermy is the need to consume far more calories relative to body size in order to maintain a constant core body temperature. Small mammals, such as moles with their rapid metabolism rates, must eat insects or other high calorie foods every half hour or so in order to stay alive.
By comparison, cold blooded rattlesnakes usually eat only once every weeks and have been known to go without food for as long as two years. Aiding in mammal body temperature control is their insulating hair and sweat glands. Sweating helps to dissipate heat by evaporative cooling. Compared to most other land mammals, humans are relatively hairless, but they have far more sweat glands. Mammals have four chambered hearts like birds , complex nervous systems, and large brains relative to the size of their bodies.
This broad range of useful features has made mammals highly adaptive and successful. They first appeared about ,, years ago , early in the age of dinosaurs , and replaced reptiles as the dominant class of land animals after 65,, years ago. As the rapidly changing environment at that time led to the mass extinction of most large reptiles, it left vast evolutionary possibilities which mammals took advantage of by rapidly diversifying through adaptive radiation.
Important to mammalian success is their reproductive system. These bones are covered by horny scutes made of keratin like human fingernails or leathery skin, depending on the species. All Canadian freshwater turtles can retreat in their shells and hide their entire body except the Common Snapping Turtle Chelydra serpentina. This shell is considered perhaps the most efficient form of armour in the animal kingdom, as adult turtles are very likely to survive from one year to the next.
Indeed, turtles have an impressively long life for such small animals. Most other species can live for more than 20 years. There are about species of turtles throughout the world, inhabiting a great variety of terrestrial, freshwater and marine ecosystems on every continent except Antarctica and its waters.
In Canada, eight native species of freshwater turtles and four species of marine turtles can be observed. Another species, the Pacific Pond Turtle Clemmys marmorata , is now Extirpated, having disappeared from its Canadian range. Also, the Eastern Box Turtle Terrapene carolina has either such a small population that it is nearly Extirpated, or the few individuals found in Canada are actually pets released in the wild.
More research is needed to know if these turtles are still native individuals. Finally, the Red-eared Slider Trachemys scripta elegans , has been introduced to Canada as released pets and, thus, is not a native species. It is significantly larger than all other marine turtles. The carapace, or upper shell, can grow to more than 2 m in length, and the turtle can weigh more than kg. Like all sea turtles, the leatherback has both front and rear flippers, but it is the only sea turtle whose flippers have no claws.
Its large front flippers are usually at least half as long as its carapace. The leatherback, like other sea turtles, cannot retract its head or flippers under its shell as tortoises and freshwater turtles can. The leatherback is also the only sea turtle that does not have a hard shell or scales. Instead, its carapace is covered with the leathery skin that gives the turtle its name. The skin covers a thick layer of oil-saturated fat and connective tissue and a matrix of small bony plates that fit together, almost like a jigsaw puzzle, to form the shell.
Its plastron, or bottom shell, is pinkish-white. Leatherbacks have a pink patch on the top of the head. Each pink spot, like a human fingerprint, is unique. Scientists are not certain what function the pink spot has, though some think it might help the turtle sense light or determine where it is located in the ocean.
The Northern Leopard Frog Lithobates pipiens is named for its leopard-like spots across its back and sides. Historically, these frogs were harvested for food frog legs and are still used today for dissection practice in biology class.
Northern Leopard Frogs are about the size of a plum, ranging from 7 to 12 centimetres. They have a variety of unique colour morphs, or genetic colour variations.
They can be different shades of green and brown with rounded black spots across its back and legs and can even appear with no spots at all known as a burnsi morph.
They have white bellies and two light coloured dorsal back ridges. Another pale line travels underneath the nostril, eye and tympanum, ending at the shoulder. The tympanum is an external hearing structure just behind and below the eye that looks like a small disk. Black pupils and golden irises make up their eyes. They are often confused with Pickerel Frogs Lithobates palustris ; whose spots are more squared then rounded and have a yellowish underbelly. Male frogs are typically smaller than the females.
Their average life span is two to four years in the wild, but up to nine years in captivity. Tadpoles are dark brown with tan tails. The western garter snake Thamnophis elegans is a medium-sized snake with a fairly robust body and long tail. From nose to tip of tail adults can measure between mm and females are larger than males.
The head of the western garter snake is large and distinct from its neck. Its crown is black or brownish, depending on which part of western Canada the snake is located. Sometimes the western garter snake is mistaken for the gopher snake or other garter snakes.
A standard way to tell the difference between garter snake species is to look at scale patterns. The western garter snake generally has 10 lower lip scales, and eight upper lip scales.
Other garter snakes usually have seven scales on the upper lip. Also, the sixth and seventh upper lip scales are usually enlarged taller than they are wide. At mid-body, this snake has 21 rows of body scales and only a single anal plate.
The scales on its back are keeled — ridged instead of smooth. There are two lateral stripes on either side of its body — on the 2nd and 3rd rows of body scales — that are similar in color to the stripe down its back. In the space between stripes, the western garter is marked with dark spots or light specks.
Like its head, its body has a grayish-green or black to dark brown colour. The western garter snake has a grey or beige underbelly colour that may have dark spots, or a dark underbelly with white flecks concentrated down the mid-line. At the same time, the Sea Otter is the largest member of its family, the mustelids, which includes River Otters, weasels, badgers, wolverines and martens. It may come to land to flee from predators if needed, but the rest of its time is spent in the ocean.
It varies in colour from rust to black. Unlike seals and sea lions, the Sea Otter has little body fat to help it survive in the cold ocean water. Instead, it has both guard hairs and a warm undercoat that trap bubbles of air to help insulate it.
The otter is often seen at the surface grooming; in fact, it is pushing air to the roots of its fur. Mollusks are invertebrates, meaning they have no bones. They are cold-blooded, like all invertebrates, and have blue, copper-based blood.
The octopus is soft-bodied, but it has a very small shell made of two plates in its head and a powerful, parrot-like beak. The Giant Pacific Octopus is the largest species of octopus in the world. Specimens have weighed as much as kg and measured 9.
The Common Raven Corvus corax is one of the heaviest passerine birds and the largest of all the songbirds. It is easily recognizable because of its size between 54 and 67 centimetres long, with a wingspan of to cm, and weighing between 0. It has a ruff of feathers on the throat, which are called 'hackles', and a wide, robust bill. When in flight, it has a wedge-shaped tail, with longer feathers in the middle. While females may be a bit smaller, both sexes are very similar.
The size of an adult raven may also vary according to its habitat, as subspecies from colder areas are often larger. A raven may live up to 21 years in the wild, making it one of the species with the longest lifespan in all passerine birds. Both birds are from the same genus order of passerine birds, corvid family —like jays, magpies and nutcrackers, Corvus genus and have a similar colouring. But the American Crow is smaller with a wingspan of about 75 cm and has a fan-shaped tail when in flight with no longer feathers.
Their cries are different: the raven produces a low croaking sound, while the crow has a higher pitched cawing cry. While adult ravens tend to live alone or in pairs, crows are more often observed in larger groups.
It can weigh up to 63, kilograms and measure up to 16 metres. Females tend to be a bit larger than males — measuring, on average, one metre longer. Its head makes up about a fourth of its body length, and its mouth is characterized by its arched, or highly curved, jaw. Its skin is otherwise smooth and black, but some individuals have white patches on their bellies and chin.
It has large, triangular flippers, or pectoral fins. Its tail, also called flukes or caudal fins, is broad six m wide from tip to tip! Unlike most other large whales, it has no dorsal fin. For a variety of reasons, including its rarity, scientists know very little about this rather large animal. For example, there is little data on the longevity of Right Whales, but photo identification on living whales and the analysis of ear bones and eyes on dead individuals can be used to estimate age.
It is believed that they live at least 70 years, maybe even over years, since closely related species can live as long. Unique characteristics. The Right Whale has a bit of an unusual name. Its name in French is more straightforward; baleine noire, the black whale. The American Lobster Homarus americanus is a marine invertebrate which inhabits our Atlantic coastal waters.
As an invertebrate, it lacks bones, but it does have an external shell, or exoskeleton, making it an arthropod like spiders and insects. Its body is divided in two parts: the cephalothorax its head and body and its abdomen, or tail. On its head, the lobster has eyes that are very sensitive to movement and light, which help it to spot predators and prey, but are unable to see colours and clear images. It also has three pairs of antennae, a large one and two smaller ones, which are its main sensory organs and act a bit like our nose and fingers.
Around its mouth are small appendages called maxillipeds and mandibles which help direct food to the mouth and chew. Lobsters have ten legs, making them decapod ten-legged crustaceans, a group to which shrimp and crabs also belong other arthropods have a different number of legs, like spiders, which have eight, and insects, which have six.
Four pairs of these legs are used mainly to walk and are called pereiopods. The remaining pair, at the front of the cephalothorax, are called chelipeds and each of those limbs ends with a claw. These claws help the lobster defend itself, but also capture and consume its prey. Each claw serves a different purpose: the bigger, blunter one is used for crushing, and the smaller one with sharper edges, for cutting. The Barn Swallow Hirundo rustica is a medium-sized songbird, about the size of a sparrow.
It measures between 15 and 18 centimeters cm in length and 29 to 32 cm in wingspan, and weighs between 15 and 20 grams g. While both reptiles and fish lay eggs, they are often very different in texture and appearance.
Reptile eggs are often hard and leathery. Fish eggs are usually rather small in comparison to reptile eggs and they are soft and transparent. Most fish and reptiles do not have maternal instincts, which means they do not care for their young once they are hatched or born. Anastasia Blackwood has been writing for publication since In , Blackwood was published in "Southern Steel" magazine—a small publication for motorcycle enthusiasts.
Blackwood is currently working towards her bachelor's degree in journalism at Central Connecticut State University. By using the site, you agree to the uses of cookies and other technology as outlined in our Policy, and to our Terms of Use.
Land Vs. Ocean Hermit Crab.
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