Mammal

qas: question: Which specific mammal is the largest today?
answers: text: blue whale

question: Which mammal is the smallest?
answers: text: bumblebee bat

question: Which four legged mammal is considered to be the smartest?
answers: text: elephants

question: About how small is the average bumble bee bat?
answers: text: 30–40 mm (1.2–1.6 in)

question: What do the largest group of mammals, elephants, have that helps the fetus during gestation?

question: How small is the average fetus?

question: What are some fetuses adapted for?

question: What is another name for a large elephant?

question: What does a placenta help bumblebee bats do?
context: Mammals include the largest animals on the planet, the rorquals and other large whales, as well as some of the most intelligent, such as elephants, primates, including humans, and cetaceans. The basic body type is a four-legged land-borne animal, but some mammals are adapted for life at sea, in the air, in trees, or on two legs. The largest group of mammals, the placentals, have a placenta, which enables feeding the fetus during gestation. Mammals range in size from the 30–40 mm (1.2–1.6 in) bumblebee bat to the 33-meter (108 ft) blue whale.

qas: question: Who coined the name "mammal" from the scientific name Mammalia?
answers: text: Carl Linnaeus

question: What do all female mammals have in common when they have children?
answers: text: nurse their young with milk

question: How many mammals were known to exist up to 2006?
answers: text: 5,416

question: How many families did mammals consist of as of 2006?
answers: text: 153 families

question: What term  did IUCN coin in 1758?

question: In 1758 how many mammal species were known?

question: What was completed by Carl Linnaeus in 2006?

question: How was the IUCN Red List grouped?

question: How many accepted species are there according to Carl Linnaeus?
context: The word "mammal" is modern, from the scientific name Mammalia coined by Carl Linnaeus in 1758, derived from the Latin mamma ("teat, pap"). All female mammals nurse their young with milk, which is secreted from special glands, the mammary glands. According to Mammal Species of the World, 5,416 species were known in 2006. These were grouped in 1,229 genera, 153 families and 29 orders. In 2008 the IUCN completed a five-year, 1,700-scientist Global Mammal Assessment for its IUCN Red List, which counted 5,488 accepted species.

qas: question: How many species of mammals do not have a live birth?
answers: text: five species

question: Which group consist of the most mammals?
answers: text: Rodentia

question: Which group do humans belong too?
answers: text: Primates

question: Which group do cats and dogs belong too?
answers: text: Carnivora

question: What do all modern monotremes give birth to?

question: What group do the six species of monotremes belong to? 

question: Which monotreme consists of the most mammals?

question: What is the monotreme that is second after Rodentia?

question: What are some examples of monotremes that are part of the group Rodentia?
context: Except for the five species of monotremes (egg-laying mammals), all modern mammals give birth to live young. Most mammals, including the six most species-rich orders, belong to the placental group. The three largest orders in numbers, are first Rodentia: mice, rats, porcupines, beavers, capybaras, and other gnawing mammals; then Chiroptera: bats; and then Soricomorpha: shrews, moles and solenodons. The next three orders, depending on the biological classification scheme used, are the Primates including the humans; the Cetartiodactyla including the whales and the even-toed hoofed mammals; and the Carnivora, that is, cats, dogs, weasels, bears, seals, and their relatives.

qas: question: From which time period did birds and reptiles began to appear from?
answers: text: Carboniferous period

question: When did non-avian dinosaurs become extinct?
answers: text: 66 million years ago

question: Which early mammalian ancestor produced non-mammalian Dimetroden?
answers: text: sphenacodont pelycosaurs

question: When did sphenacodont pelycosaurs become extinct?

question: What were the modern mammalian orders ancestors called?

question: At the end of the synapsid period what non-mammal was produced?

question: The Sphenacodontia arose in the Paleogene and Neogene periods of what era?

question: At the end of the Carboniferous period what did the Neogene diverge from that led to today's reptiles and birds?
context: The early synapsid mammalian ancestors were sphenacodont pelycosaurs, a group that produced the non-mammalian Dimetrodon. At the end of the Carboniferous period, this group diverged from the sauropsid line that led to today's reptiles and birds. The line following the stem group Sphenacodontia split-off several diverse groups of non-mammalian synapsids—sometimes referred to as mammal-like reptiles—before giving rise to the proto-mammals (Therapsida) in the early Mesozoic era. The modern mammalian orders arose in the Paleogene and Neogene periods of the Cenozoic era, after the extinction of the non-avian dinosaurs 66 million years ago.

qas: question: Who defined mammalian as the crown group mammals?
answers: text: Timothy Rowe

question: By Rowe's definition, when did he start to exclude animals?
answers: text: Triassic

question: Which group do marsupials and placentals belong to?
answers: text: therian mammals

question: How did Timothy Rowe define Mammalia in the mid 19th century?

question: What are two examples of the most recent ancestor of the Jurassic period?

question: In what period did mammals live?

question: For how long have Juassic fossils been referred to the Mammalia?

question: What is one thing Triassic fossils are shown to consist of according to a 19th century paper?
context: In an influential 1988 paper, Timothy Rowe defined Mammalia phylogenetically as the crown group mammals, the clade consisting of the most recent common ancestor of living monotremes (echidnas and platypuses) and therian mammals (marsupials and placentals) and all descendants of that ancestor. Since this ancestor lived in the Jurassic period, Rowe's definition excludes all animals from the earlier Triassic, despite the fact that Triassic fossils in the Haramiyida have been referred to the Mammalia since the mid-19th century.

qas: question: Which group are Ambondro's closely related to?
answers: text: monotremes

question: Which two groups are closely related to therian mammals?
answers: text: Amphilestes and Amphitherium

question: How many years do momotremes and therian mammals go back?
answers: text: 167 million years

question: About what year do synapsid date back to?
answers: text: 225 Ma

question: What is the earliest Ambondro that satisfies Kemp's definitions?

question: What is Tikitherium more closely related to more than therian mammals?

question: What time period are fossils of the ambondro dated to in the Middle Jurassic?

question: About what year are ambondro dated to?

question: What can the appearance of genera be broadly given?
context: If Mammalia is considered as the crown group, its origin can be roughly dated as the first known appearance of animals more closely related to some extant mammals than to others. Ambondro is more closely related to monotremes than to therian mammals while Amphilestes and Amphitherium are more closely related to the therians; as fossils of all three genera are dated about 167 million years ago in the Middle Jurassic, this is a reasonable estimate for the appearance of the crown group. The earliest known synapsid satisfying Kemp's definitions is Tikitherium, dated 225 Ma, so the appearance of mammals in this broader sense can be given this Late Triassic date. In any case, the temporal range of the group extends to the present day.

qas: question: Who wrote the "Principles of Classification and a Classification of Mammals?
answers: text: George Gaylord Simpson

question: Simpson laid the systematics of mammal origins and was taught universally up until the end of what century?
answers: text: 20th

question: Which new concept has greatly taken over Simpsons much debated theoretical systematization?
answers: text: cladistics

question: What did Simpson lay out that was universally taught until 1945?

question: What was the original source for the paleontoligical record?

question: What happened since the classification by the AMNH?

question: What taxonomy took over AMNH's debated systematization?

question: Up until what century were cladistics universally taught?
context: George Gaylord Simpson's "Principles of Classification and a Classification of Mammals" (AMNH Bulletin v. 85, 1945) was the original source for the taxonomy listed here. Simpson laid out a systematics of mammal origins and relationships that was universally taught until the end of the 20th century. Since Simpson's classification, the paleontological record has been recalibrated, and the intervening years have seen much debate and progress concerning the theoretical underpinnings of systematization itself, partly through the new concept of cladistics. Though field work gradually made Simpson's classification outdated, it remained the closest thing to an official classification of mammals.

qas: question: In 1997 who revised the classification of mammals?
answers: text: Malcolm C. McKenna and Susan K. Bell

question: Where did the two authors work together as paleontologist? 
answers: text: American Museum of Natural History

question: From whom did McKenna inherit the project from?
answers: text: Simpson

question: Who did Simpson inherit the project from?

question: What happened to molecular genetic data in 1997?

question: What was the book written by Simpson?

question: What information about mammals does Simpson's book cover?

question: What did Simpson help construct with Bell?
context: In 1997, the mammals were comprehensively revised by Malcolm C. McKenna and Susan K. Bell, which has resulted in the McKenna/Bell classification. Their 1997 book, Classification of Mammals above the Species Level, is the most comprehensive work to date on the systematics, relationships, and occurrences of all mammal taxa, living and extinct, down through the rank of genus, though recent molecular genetic data challenge several of the higher level groupings. The authors worked together as paleontologists at the American Museum of Natural History, New York. McKenna inherited the project from Simpson and, with Bell, constructed a completely updated hierarchical system, covering living and extinct taxa that reflects the historical genealogy of Mammalia.

qas: question: Through Molecular studies, what was used to suggest new relationships among mammal families?
answers: text: DNA analysis

question: During these Molecular studies, which three major groups of mammals shared a common ancestors from the Cretaceous period?
answers: text: Afrotheria, Xenarthra, and Boreoeutheria

question: Afrotheria,Xenartha, and Boreoeutheria deprives from which two lineages?
answers: text: Euarchontoglires and Laurasiatheria

question: What have studies based on Boreoeutheria suggested?

question: What have findings based on common ancestors in the Cretaceous been validated by?

question: What are three major groups of Laurasiatheria?

question: Where did Euarchontoglires and Laurasiatheria come from?

question: What two major common ancestors does Alantogenata contain?
context: Molecular studies based on DNA analysis have suggested new relationships among mammal families over the last few years. Most of these findings have been independently validated by retrotransposon presence/absence data. Classification systems based on molecular studies reveal three major groups or lineages of placental mammals- Afrotheria, Xenarthra, and Boreoeutheria- which diverged from early common ancestors in the Cretaceous. The relationships between these three lineages is contentious, and all three possible different hypotheses have been proposed with respect to which group is basal with respect to other placentals. These hypotheses are Atlantogenata (basal Boreoeutheria), Epitheria (basal Xenarthra), and Exafroplacentalia (basal Afrotheria). Boreoeutheria in turn contains two major lineages- Euarchontoglires and Laurasiatheria.

qas: question: From which period did the first known amniotes arise from?
answers: text: Carboniferous

question: From which group did amniotes descendents of?
answers: text: reptiliomorph amphibious tetrapods

question: Two important Amniotes  lineages became distinct, what was the name of that distinction?
answers: text: the synapsids

question: Sauropsids would later include which other animals into its group?
answers: text: turtles, lizards, snakes, crocodilians, dinosaurs and birds

question: What is a distinct trait of Synapsids?
answers: text: single hole (temporal fenestra) low on each side of the skull

question: From what period did the first insects come from?

question: What already inhabited the synapsids?

question: When did amphibious tetrapods become prominent?

question: What do amniotes have on each side of the skull?

question: What animals were later included in the carboniferous group?
context: The first amniotes apparently arose in the Late Carboniferous. They descended from earlier reptiliomorph amphibious tetrapods, which lived on land that was already inhabited by insects and other invertebrates as well as by ferns, mosses and other plants. Within a few million years, two important amniote lineages became distinct: the synapsids, which would later include the common ancestor of the mammals; and the sauropsids, which would eventually come to include turtles, lizards, snakes, crocodilians, dinosaurs and birds. Synapsids have a single hole (temporal fenestra) low on each side of the skull.

qas: question: From which dinosaur group did Therapsids descend from?
answers: text: pelycosaurs

question: Around what time did Therapsids become the dominant land animal?
answers: text: 265 million years ago

question: At which group did Therapsids end with?
answers: text: probainognathian cynodonts

question: When did basal eupelycosaurs descend from pelycosaurs?

question: What did the therapsid lineage do in the Middle Permian, 265 million years ago?

question: How do Probainognathian cynodonts differ from the therapsid lineage?

question: What are some characteristics that show how mammals differ from pelycosaurs?

question: What animal was at the end stage of the Middle Permian?
context: Therapsids descended from pelycosaurs in the Middle Permian, about 265 million years ago, and became the dominant land vertebrates. They differ from basal eupelycosaurs in several features of the skull and jaws, including: larger temporal fenestrae and incisors which are equal in size. The therapsid lineage leading to mammals went through a series of stages, beginning with animals that were very like their pelycosaur ancestors and ending with probainognathian cynodonts, some of which could easily be mistaken for mammals. Those stages were characterized by:

qas: question: What was the name of extinction level event that ended the dominance of the carnivores among therapsids?
answers: text: Permian–Triassic

question: During which time period did archosaurs begin to take over as the dominant carnivore?
answers: text: Triassic

question: Which three groups did the early Triassic period consist of?
answers: text: crocodylomorphs, the pterosaurs, and the dinosaurs

question: During the Jurassic period which group came out as the most dominate for both carnivores and herbivores?
answers: text: dinosaurs

question: Why was the Jurassic a prolonged event?

question: What did the Jurassic period end?

question: What was taken over by carnivores in the Permian-Triassic?

question: What types of animals were included in the Permian-Triassic over 35 million years?

question: What had archosaurs come to dominate by the Jurassic?
context: The Permian–Triassic extinction event, which was a prolonged event due to the accumulation of several extinction pulses, ended the dominance of the carnivores among the therapsids. In the early Triassic, all the medium to large land carnivore niches were taken over by archosaurs which, over an extended period of time (35 million years), came to include the crocodylomorphs, the pterosaurs, and the dinosaurs. By the Jurassic, the dinosaurs had come to dominate the large terrestrial herbivore niches as well.

qas: question: What is the oldest know fossil among the Eutheria group? 
answers: text: shrewlike Juramaia sinensis

question: How long ago does oldest know fossil date back to?
answers: text: 160 million years ago

question: In what time period did early animals share some features with marsupials?
answers: text: 125 million years ago

question: Which lineage were some of these early marsupial features were lost?
answers: text: placental

question: What is the oldest known feature among the marsupials?

question: What time period is a marsupial dated to in the Early Cretaceous?

question: What do Juramaia have in common with placentals?

question: What lineage shows some early eutherian features were lost?

question: When was the marsupial mother from the Cretaceous dated to?
context: The oldest known fossil among the Eutheria ("true beasts") is the small shrewlike Juramaia sinensis, or "Jurassic mother from China", dated to 160 million years ago in the Late Jurassic. A later eutherian, Eomaia, dated to 125 million years ago in the Early Cretaceous, possessed some features in common with the marsupials but not with the placentals, evidence that these features were present in the last common ancestor of the two groups but were later lost in the placental lineage. In particular:

qas: question: How long ago did most placental orders diverge from?
answers: text: 100 to 85 million years ago

question: Which two major time periods did placentals appear?
answers: text: Eocene through the Miocene

question: Which time period did early highly undisputed fossils of placental mammals appear?
answers: text: Paleocene

question: When is the earliest know primate thought to had exist?
answers: text: 55 million years ago

question: How much did the first primate weigh?
answers: text: 20–30 grams (0.7–1.1 ounce)

question: Where do the earliest fossils of the Miocene come from?

question: What have scientists identified Eocene as?

question: What is the earliest ancestor of humans from about 55 million years ago?

question: How much did the Protungulatum donnae weigh?

question: What do scientists object about primates before the end of the Paleocene?
context: Recent molecular phylogenetic studies suggest that most placental orders diverged about 100 to 85 million years ago and that modern families appeared in the period from the late Eocene through the Miocene. But paleontologists object that no placental fossils have been found from before the end of the Cretaceous. The earliest undisputed fossils of placentals come from the early Paleocene, after the extinction of the dinosaurs. In particular, scientists have recently identified an early Paleocene animal named Protungulatum donnae as one of the first placental mammals. The earliest known ancestor of primates is Archicebus achilles from around 55 million years ago. This tiny primate weighed 20–30 grams (0.7–1.1 ounce) and could fit within a human palm.

qas: question: When is it believed that the earliest know hair was said to exist?
answers: text: 164 million years ago

question: When was it suggested that foramina premaxillae could contain the first know hairs?
answers: text: 1950s

question: Which major time period were these suggested hairs from?
answers: text: Jurassic

question: What type of fossils showed the earliest evidence of cynodonts?

question: What was suggested about the Tupinambis in the Thrinaxodon in the 1950's?

question: What do popular sources attribute foramina to?

question: At what time is it believed the earliest known foramina existed?

question: What does the modern lizard Castorocauda have?
context: The earliest clear evidence of hair or fur is in fossils of Castorocauda, from 164 million years ago in the Middle Jurassic. In the 1950s, it was suggested that the foramina (passages) in the maxillae and premaxillae (bones in the front of the upper jaw) of cynodonts were channels which supplied blood vessels and nerves to vibrissae (whiskers) and so were evidence of hair or fur; it was soon pointed out, however, that foramina do not necessarily show that an animal had vibrissae, as the modern lizard Tupinambis has foramina that are almost identical to those found in the nonmammalian cynodont Thrinaxodon. Popular sources, nevertheless, continue to attribute whiskers to Thrinaxodon.

qas: question: Which group of animal has a lower body temperature that marsupials and placentals?
answers: text: monotremes

question: Which time period is suggested that cynodonts had a high metabolic rate?
answers: text: Triassic

question: Why is it necessary for smaller animals to have an insulative covering?
answers: text: maintenance of a high and stable body temperature

question: What does evidence found suggest about monotremes?

question: What do therians need to maintain a stable body temperature?

question: What do small animals have compared to therians?

question: What suggests that monotremes have high metabolic rates?

question: What do placentals use their fur covering for?
context: When endothermy first appeared in the evolution of mammals is uncertain. Modern monotremes have lower body temperatures and more variable metabolic rates than marsupials and placentals, but there is evidence that some of their ancestors, perhaps including ancestors of the therians, may have had body temperatures like those of modern therians. Some of the evidence found so far suggests that Triassic cynodonts had fairly high metabolic rates, but it is not conclusive. For small animals, an insulative covering like fur is necessary for the maintenance of a high and stable body temperature.

qas: question: When air enters both the oral and nasal cavities, where does it flow through?
answers: text: larynx, trachea and bronchi

question: Increasing pressure on the diaphragm thus increasing air output more frequently is usually caused by?
answers: text: exercise

question: A result of air being sucked into or blown out of the lung thats moving its pressure gradient is referred to?
answers: text: bellows lung

question: Where did the term Bellows Lung come from?
answers: text: blacksmith's bellows

question: When mammals take oxygen into their relaxed diaphragm, what happens to the abdominal wall?

question: What is alveoli inspired by?

question: What is the ribcage able to passively recoil?

question: What does contraction of the thorax do while increasing the volume of the lung cavity?

question: When air enters the nasal cavity, what does the rib cage expand?
context: Breathing is largely driven by the muscular diaphragm, which divides the thorax from the abdominal cavity, forming a dome with its convexity towards the thorax. Contraction of the diaphragm flattens the dome, increasing the volume of the cavity in which the lung is enclosed. Air enters through the oral and nasal cavities; it flows through the larynx, trachea and bronchi and expands the alveoli. Relaxation of the diaphragm has the opposite effect, passively recoiling during normal breathing. During exercise, the abdominal wall contracts, increasing visceral pressure on the diaphragm, thus forcing the air out more quickly and forcefully. The rib cage itself also is able to expand and contract the thoracic cavity to some degree, through the action of other respiratory and accessory respiratory muscles. As a result, air is sucked into or expelled out of the lungs, always moving down its pressure gradient. This type of lung is known as a bellows lung as it resembles a blacksmith's bellows. Mammals take oxygen into their lungs, and discard carbon dioxide.

qas: question: What is the typical thickness of the epidermis?
answers: text: 10 to 30 cells thick

question: What is the main function of the epidermis?
answers: text: to provide a waterproof layer

question: How much more thicker is the dermis to the epidermis?
answers: text: 15 to 40 times thicker

question: What is the dermis mainly consist of?
answers: text: bony structures and blood vessels

question: What does the Hyperdermis consist of?
answers: text: adipose tissue

question: When the hypodermis is 10 to 30 cells thick, what is its main function?

question: What happens to the outermost cells of the hypodermis?

question: How do the bottommost cells of the hypodermis act?

question: How much thicker is the hypodermis from the dermis?

question: What are two components that make up the epidermis?
context: The epidermis is typically 10 to 30 cells thick; its main function is to provide a waterproof layer. Its outermost cells are constantly lost; its bottommost cells are constantly dividing and pushing upward. The middle layer, the dermis, is 15 to 40 times thicker than the epidermis. The dermis is made up of many components, such as bony structures and blood vessels. The hypodermis is made up of adipose tissue. Its job is to store lipids, and to provide cushioning and insulation. The thickness of this layer varies widely from species to species.

qas: question: What is another name used for mammalian hair?
answers: text: pelage

question: Which color of hair is most common among mammalian taxa?
answers: text: Light-dark color

question: Besides Camouflage being a reason for having certain hair colors, what other reasons have been discovered? 
answers: text: sexual selection, communication, and physiological processes

question: What is another name for camouflage?

question: How does intraspecies communication vary?

question: What is distribution of loci common in?

question: Why do selective pressures favor arctic environments?

question: What three examples show how hormone levels are important in the mate selection process?
context: Mammalian hair, also known as pelage, can vary in color between populations, organisms within a population, and even on the individual organism. Light-dark color variation is common in the mammalian taxa. Sometimes, this color variation is determined by age variation, however, in other cases, it is determined by other factors. Selective pressures, such as ecological interactions with other populations or environmental conditions, often lead to the variation in mammalian coloration. These selective pressures favor certain colors in order to increase survival. Camouflage is thought to be a major selection pressure shaping coloration in mammals, although there is also evidence that sexual selection, communication, and physiological processes may influence the evolution of coloration as well. Camouflage is the most predominant mechanism for color variation, as it aids in the concealment of the organisms from predators or from their prey. Coat color can also be for intraspecies communication such as warning members of their species about predators, indicating health for reproductive purposes, communicating between mother and young, and intimidating predators. Studies have shown that in some cases, differences in female and male coat color could indicate information nutrition and hormone levels, which are important in the mate selection process. One final mechanism for coat color variation is physiological response purposes, such as temperature regulation in tropical or arctic environments. Although much has been observed about color variation, much of the genetic that link coat color to genes is still unknown. The genetic sites where pigmentation genes are found are known to affect phenotype by: 1) altering the spatial distribution of pigmentation of the hairs, and 2) altering the density and distribution of the hairs. Quantitative trait mapping is being used to better understand the distribution of loci responsible for pigmentation variation. However, although the genetic sites are known, there is still much to learn about how these genes are expressed.

qas: question: What is the common mammal group that gives birth to live young?
answers: text: viviparous

question: How many species of mammals lay eggs?
answers: text: five species

question: Which mammal that has the bill of a duck lays eggs?
answers: text: platypus

question: The platypus has sex chromosomes more related to which other non-mammal?
answers: text: chicken

question: What makes most monotreme viviparous?

question: What do marsupials have that is different from most mammals?

question: How many species of mammals give birth to live young?

question: What are some characteristics of young chickens?

question: What do marsupials have that make them less like a therian?
context: Most mammals are viviparous, giving birth to live young. However, the five species of monotreme, the platypuses and the echidnas, lay eggs. The monotremes have a sex determination system different from that of most other mammals. In particular, the sex chromosomes of a platypus are more like those of a chicken than those of a therian mammal. Like marsupials and most other mammals, monotreme young are larval and fetus-like, as the presence of epipubic bones prevents the expansion of the torso, forcing them to produce small young.

qas: question: Which sub class are most viviparous mammals in?
answers: text: Theria

question: Viviparous mammals today are in which two main infraclasses?
answers: text: marsupial and placental

question: What is present in all non-placental mammals?
answers: text: epipubic bones

question: What sub class are most placental eutherians in?

question: What class are placental eutherians in today?

question: Where on the mother are the epipubic bones located?

question: What prevents a short gestation period in full pregnancy?

question: In marsupials what is a plesyomorphic condition shorter than?
context: Viviparous mammals are in the subclass Theria; those living today are in the marsupial and placental infraclasses. A marsupial has a short gestation period, typically shorter than its estrous cycle, and gives birth to an undeveloped newborn that then undergoes further development; in many species, this takes place within a pouch-like sac, the marsupium, located in the front of the mother's abdomen. This is the plesyomorphic condition among viviparous mammals; the presence of epipubic bones in all non-placental mammals prevents the expansion of the torso needed for full pregnancy. Even non-placental eutherians probably reproduced this way.

qas: question: Which part is larger relative to the brain in primates?
answers: text: cerebrum

question: Which non-primate has the ability to learn and perform new task?
answers: text: Rats

question: Mammals with smaller brains tend to be in what class in the food chain?
answers: text: prey

question: What part of the brain is larger in rats compared to the rest of the brain?

question: With primates, what is related to intelligence?

question: What are two indications of a larger cerebrum?

question: What are cats able to do when they find a new home?

question: What is one thing that shows a cat has a large cerebrum?
context: In intelligent mammals, such as primates, the cerebrum is larger relative to the rest of the brain. Intelligence itself is not easy to define, but indications of intelligence include the ability to learn, matched with behavioral flexibility. Rats, for example, are considered to be highly intelligent, as they can learn and perform new tasks, an ability that may be important when they first colonize a fresh habitat. In some mammals, food gathering appears to be related to intelligence: a deer feeding on plants has a brain smaller than a cat, which must think to outwit its prey.

qas: question: To be able to maintain a constant body temperature, what do mammals need to maintain?
answers: text: nutritious and plentiful diet

question: What does a omnivore imply?
answers: text: eats both prey and plants

question: What do the majority of mammals under 18 oz eat?
answers: text: insects

question: What determines a mammals diet type?
answers: text: The size

question: What do herbivores use to maintain a high level of bacteria for digestion?

question: What do herbivores have because they don't need specialized digestion?

question: What is a factor that determines body temperature?

question: What lives in an omnivores digestive tract?

question: Where are bacteria for digestion housed in an omnivore?
context: To maintain a high constant body temperature is energy expensive – mammals therefore need a nutritious and plentiful diet. While the earliest mammals were probably predators, different species have since adapted to meet their dietary requirements in a variety of ways. Some eat other animals – this is a carnivorous diet (and includes insectivorous diets). Other mammals, called herbivores, eat plants. A herbivorous diet includes subtypes such as fruit-eating and grass-eating. An omnivore eats both prey and plants. Carnivorous mammals have a simple digestive tract, because the proteins, lipids, and minerals found in meat require little in the way of specialized digestion. Plants, on the other hand, contain complex carbohydrates, such as cellulose. The digestive tract of an herbivore is therefore host to bacteria that ferment these substances, and make them available for digestion. The bacteria are either housed in the multichambered stomach or in a large cecum. The size of an animal is also a factor in determining diet type. Since small mammals have a high ratio of heat-losing surface area to heat-generating volume, they tend to have high energy requirements and a high metabolic rate. Mammals that weigh less than about 18 oz (500 g) are mostly insectivorous because they cannot tolerate the slow, complex digestive process of a herbivore. Larger animals, on the other hand, generate more heat and less of this heat is lost. They can therefore tolerate either a slower collection process (those that prey on larger vertebrates) or a slower digestive process (herbivores). Furthermore, mammals that weigh more than 18 oz (500 g) usually cannot collect enough insects during their waking hours to sustain themselves. The only large insectivorous mammals are those that feed on huge colonies of insects (ants or termites).

qas: question: What is the name given when zones of gradation exits?
answers: text: clines

question: What is the given name of a lion and tiger hybrid?
answers: text: liger

question: What is the marketed name given in the meat industry when you involve a european or indian domestic cattle mixed with an American bison?
answers: text: Beefalo

question: What is the given name of a offspring from two different animals?
answers: text: hybrid

question: What is a zone of resilience referred to as?

question: What does it mean when closely related species exhibit greater strength and resilience than their parents?

question: What are some examples that show how strength and resilience is maintained in related species?

question: Why are ligers more fertile than donkeys?

question: Where is an American bison sometimes used to entertain people?
context: The deliberate or accidental hybridising of two or more species of closely related animals through captive breeding is a human activity which has been in existence for millennia and has grown in recent times for economic purposes. The number of successful interspecific mammalian hybrids is relatively small, although it has come to be known that there is a significant number of naturally occurring hybrids between forms or regional varieties of a single species.[citation needed] These may form zones of gradation known as clines. Indeed, the distinction between some hitherto distinct species can become clouded once it can be shown that they may not only breed but produce fertile offspring. Some hybrid animals exhibit greater strength and resilience than either parent. This is known as hybrid vigor. The existence of the mule (donkey sire; horse dam) being used widely as a hardy draught animal throughout ancient and modern history is testament to this. Other well known examples are the lion/tiger hybrid, the liger, which is by far the largest big cat and sometimes used in circuses; and cattle hybrids such as between European and Indian domestic cattle or between domestic cattle and American bison, which are used in the meat industry and marketed as Beefalo. There is some speculation that the donkey itself may be the result of an ancient hybridisation between two wild ass species or sub-species. Hybrid animals are normally infertile partly because their parents usually have slightly different numbers of chromosomes, resulting in unpaired chromosomes in their cells, which prevents division of sex cells and the gonads from operating correctly, particularly in males. There are exceptions to this rule, especially if the speciation process was relatively recent or incomplete as is the case with many cattle and dog species. Normally behavior traits, natural hostility, natural ranges and breeding cycle differences maintain the separateness of closely related species and prevent natural hybridisation. However, the widespread disturbances to natural animal behaviours and range caused by human activity, cities, dumping grounds with food, agriculture, fencing, roads and so on do force animals together which would not normally breed. Clear examples exist between the various sub-species of grey wolf, coyote and domestic dog in North America. As many birds and mammals imprint on their mother and immediate family from infancy, a practice used by animal hybridizers is to foster a planned parent in a hybridization program with the same species as the one with which they are planned to mate.