Rodents: From Busy Beavers to Suicidal Lemmings Quiz

Answer: forty percent

Close to half of all species of mammals are rodents. Rodents are native to all continents except Antarctica, and are found in every area where humans live. They live in pretty much every habitat; trees, ground nests, underground burrows, and semi aquatic environs. Commonly known rodents include mice, rats, squirrels, beavers, gophers, groundhogs, porcupines, hamsters and guinea pigs.

Answer: the beaver

Sexual dimorphism is the inclusive term for physiological and behavioral differences between males and females of a given species. Perhaps you got the correct answer even without knowing the size difference, as the beaver is the only rodent among the answers. Beavers are the second largest rodent species. Males and females are similar, with females tending to be slightly heavier. Most people, through their own experience and observation, can see that human males and male dogs tend to be larger than their female counterparts on average, notwithstanding the case of American woman Sarah Elaine Allen (1955-2008), who was listed in the Guinness record book at 7'7" tall.

In other large primates, such as gorillas, orangutans, and baboons, size disparity is greatest, with males normally being up to twice as large.

Answer: competition over who has the longer tail

Tail length is related to ecological profile, not behavior, although tail movements clearly are part of squirrel communication. Tree squirrels and flying squirrels tend to have longer tails, ground squirrels shorter ones. Young squirrels, like most mammal young, enjoy play; adult squirrels, again like most animals, have complex mating patterns which usually involve pursuit. Most commonly observable squirrel chasing is a more dominant individual driving a weaker one away from its territory or food source.

Answer: The bush rat is not a rat

The bush rat IS a rat; a small, omniverous, rodent indigenous to Australia. It is one of the more common rat species in Australia, and can be found chiefly in the southeast coastal regions. The three incorrect answers are true statements. Interesting that "wombat" and "numbat" are names for real Australian mammals, but they have no connection to the flying mammals known as bats.

A good look at a wombat shows a chubby ground dwelling marsupial approximately one meter long, with a face and ears reminiscent of a kangaroo or a koala, both of which are relatives. Wombats are herbivores with powerful claws for digging and sharp teeth.

Despite their cuddly appearance, they can be aggressive and can move remarkably fast. The numbat, aka the walpurti or banded anteater, is a small marsupial mammal native to Western Australia.

It has grey/brown fur and eats mainly termites. Despite its name and its mousey appearance, the musky rat-kangaroo is not a rat, or a mouse, or a kangaroo! It is a small marsupial found only in the rain forests of north eastern Australia.

Answer: prairie dogs and chipmunks

Prairie dogs, as most zoo goers are aware, are not dogs but herbivorous, burrowing rodents native to North American grassland plains. Like chipmunks, they are cousins of the common squirrel. Since at least from "The Taming of the Shrew", written by Shakespeare sometime in the early 1590s, shrews, like rats, have gotten a lot of bad publicity, but they are not rodents.

They are classed with moles, and have a similar diet of insects, slugs and worms. A shrike is actually a medium sized bird, notable here only because it is a ruthless and efficient hunter of small rodents.

It kills said rodents by pecking their necks or skulls until they are immobilized, then eats them piecemeal. Rabbits and hares used to be included as rodents, but have been reclassified into their own order, lagomorpha, chiefly because of different tooth structure and divergent ancestry. hedge hogs, like shrews, are members of the order Eulipothypia (literal meaning: fat and blind). Genetic advances have caused some animal re-classifications by showing how closely or distantly related are various species.

Answer: Voles are rodents, moles are not rodents

These two garden dwelling mammals with the rhyming names are often confused. Both dig in lawns and are often considered to be pests. You may first notice the ridges or ruts parting your grass or see tunnels in the snow. Voles are rodents, and look like fat mice with shorter tails.

They are primarily herbivorous, preferring a diet of roots, bulbs, bark and seeds. They live above ground in dense, low lying vegetation. Moles are not rodents. They are in the order Eulipotyphla, along with shrews and hedgehogs.

They have pointed snouts, large, clawed front feet for digging, and tiny almost invisible eyes and ears. They live underground and feed on bugs, grubs and worms. The taxonomy of these burrowing mammals is complex, with behavioral characteristics, ecology, and genetics leading to differing, evolving, and sometimes conflicting classifications.

Answer: incisors grow continuously throughout my life

A rat's incisors are the four sharp, front-most teeth in its mouth; two on top, and two on the bottom. These two pairs of incisors are common to all rodents. They are efficiently evolved for gnawing just about anything. Its remaining teeth, molars, are the ones used for grinding up food prior to swallowing.

The incisors' orange/yellow hue is naturally due to the presence of iron in the pigment, and the color deepens in a few weeks after birth, especially the upper incisors. These teeth are also open rooted, which means they are always growing, and in fact would grow in an arced fashion back into the rat's mouth if it didn't constantly wear them down by gnawing on things.

Answer: The scenes of lemmings jumping into the sea were staged; lemming suicide is a myth.

All authoritative sites, from alaska.gov to Wiki, agree that the animal behavior in this film was staged, and essentially created a myth about lemmings that persists to this day. Lemmings do not commit mass suicide by jumping off cliffs or any other activity. Like many other animals, their population fluctuates greatly, depending on environmental conditions such as availability of food.

When increasing numbers overwhelm their location, they can and do migrate, crowding up against rivers or lakes, eventually swimming across in packs, and sustaining some drowning deaths.

The movie in question covers a variety of animal behavior purportedly in the Canadian Arctic region. In fact, the lemming sequence was filmed in Alberta, a landlocked province where lemmings do not live.

The "sea" they appeared to jump into was actually the Bow River. The film makers paid Inuit kids to collect lemmings, then set up snow covered turntables to spin them around and get them moving. Clever editing made the numbers appear much larger than they were. According to cameramen interviewed decades later, in the final egregious deception, the rodents were then thrown off the cliff to further the story. Whether Walt Disney himself was aware of the shenanigans is unknown, but the ethics of his "documentaries" can certainly be questioned.

Answer: Its urine is five times more concentrated than man's

The kangaroo rat is the common name of any one of several species of rodent native to the US southwest and Mexico. Its only connection to Australia is its kangaroo name, applied because of its long hind legs. This adaptation allows it to jump long distances looking for food and water.

It also has specialized complex kidneys for extracting water from its urine, and oily skin which doesn't sweat, aiding its ability to survive for long periods with no water. Additionally, these critters have large fur-lined cheek pouches for storing lots of seeds, another method of preserving moisture in a dry environment.

The largest rodent is the South American capybara, which can grow to 1.5 meters in length and weigh in excess of 60 kilograms. This dwarfs the kangaroo rat, which averages 9-10 centimeters long, and wants no part of snakes.

Answer: a rodent found in Argentina

The Patagonian mara is a larger, herbivorous, rabbit-like rodent found on the open plains of the Patagonian region in Argentina. Adults rage in size from 8-16 kilos. These animals are monogamous, and stay paired for life. Females spend the majority of their time foraging for food (to support child bearing and rearing activities). Males follow the female around, marking territory and staying vigilant for predators (foxes, wolverines, birds of prey, felids).