Mammal Test
When and where did our species evolve?
Africa 200,000 - 150,000 years ago
The characteristic traits were selected primarily for what type of lifestyle?
Arboreal
What characteristics are diagnostic of primates?
Arboreal (New World Monkeys) New World Monkeys evolved a 5th arm (tail) Nostrils open outwards or upwards (New World Monkeys)
Rabbits are ancestral to which order of mammals?
Artiodactyla
Which animal was the last to evolve?
Birds
Mammals evolved during the time when dinosaurs ruled. When the dinosaurs became extinct why did the mammals "inherit the earth" and not the birds?
Birds can only be so big and still fly
When did mammals radiate?
Cenozoic
Why is the heterogametic sex female in reptiles and birds but male in mamals?
Chance
What type of adaptations are necessary for myrmecophagy?
Long sticky tongue, reduction in size of teeth or loss of teeth, elongated and thinner jaws
Why are so many mammals nocturnal?
Maintaining body temperature, avoid dinosaurs, evolved as night-active animals hearing and sense of smell were more important than vision
What mammals are not placental?
Monotremata, Marsupials
What factors are conducive to communal hunting?
Most successful when prey are large, dangerous, and abundant
How do bats discriminate between the echoes of their own call and those of other bats?
Neural sensitization to their sonar wavelengths
The tail is a grasping limb in what type of monkeys?
New world
Why is it incorrect to view man as the good of evolution?
No predetermined goal No goals involved in evolution
What is the colonization pattern of the hominidae?
Oldest of our species in East Africa 200,000 years ago Australia-- 50,000 years ago Asia -- 40,000 years ago Europe -- 30,000 years ago North America/New World 10,000 years ago
How are jaws of carnivores designed to deal with struggling prey?
Overlapping of upper and lower teeth locks them and prevents dislocation of the jaw
What was the last (most recent) place colonized by humans?
Pacific 4,000 years ago
What are marsupials?
Pouched mammals
What are the differences in reproductive strategies between the Prototherians, Metatherians, and Eutherians?
Pre and Post natal care
What is the phylogeny of mammals (monophyletic-diphyletic-polyphyletic)?
Prototherians (subclass) Therians (subclass) Metatherians (infraclass) Eutherians (infraclass)
What are characteristics of primates are related to motor adaptations?
Retention of limb structure, five digits, mobility of limbs with unfused radius and fibula. Evolution of mobile, grasping digits, sensitive friction pads, nails. Retention of tail as an organ of balance and grasping limb
How are rabbits and rodents alike in their detention and how do they differ?
Rodents have peg-like incisors directly behind first Rabbits have incisors in their upper jaw Rodents and rabbits both have diastema
Why is sex reversal wide spread in anamniotes but absent in amniotes?
Sex reversal in anaminotes is wide spread because of morphological compatibility of "sex chromosomes" and simliarity of male/female gonads. Sex determination in amniotes is rigidly fixed because of behavioral complexity of parental care is more developed and gonads of males and females are more complex and distinct
What kinds of mammals were around during the time they were sympatric with the dinosaurs?
Shrew-like insectivores
Who were the ancestors of the mammal?
Synapsids --> Therapsids
According to Maderson what was the initial function of hair in the first mammals?
Tactile mechanoreceptors (Vibrissae)
What are eutherians?
Vivaparous placental mammals
How are each of the following modes of hunting adaptive?
speculation, stalking, ambushing, disguise, pursuit, exhausting dangerous prey, scavenging and cleopatrism
What are the benefits and problems associated with each strategy?
Fetal rejection in uterus due to alien protein from alien genes
What are general characteristics for primates?
Lengthened period of maturation, infant dependency, and gestation. Long life span. Large complex brain
When did the first homo sapiens evolve?
200,000 ya
When did bipedality evolve?
4 million years ago.
How many years ago did primates first arise?
60 mya
What is the percentage of identical genes do we share with Chimpanzees?
99%
What is the phylogeny of the family hominidae?
A. afarensis --> A. robustus --> A. africaneo A. afarensis --> Homo habilis --> Homo sapiens
Which species is our closes living relative?
Chimpanzee
What was the climate like during the cenozoic?
Cool and dry
What are the evolutionary implications or predators preying on the weak, sick, old, young, and conspicuous?
Cost effective, more caught, easier to isolate, and elimination of genes for inferior traits.
What is myrmecophagy?
Eating ants and termites
What are monotremes?
Egg-laying mammals
What is the most probable hypothesis concerning the invasion of marsupials into Australia?
Evolved in South America and got to Australia through Antarctica when Gondwanaland was together
What are characteristics of primates related to sensory adaptations?
Forward eyes for stereoscopic vision
What strategies do prey use to avoid being captured?
Grouping, speed, stay near towns, camouflage, alert signal
What behavioral strategies do predators use to capture prey?
Grouping, stealth, sneaking, speed
What are some of the diagnostic characters of class mammalia?
Hair, Mammary glands, Diphydont teeth, Muscular Diaphragm
Mammalian endothermy is economical because of what anatomical characteristics?
Hair, sweat glands, four-chambered heart, negative pressure lungs
What kind of teeth did the first mammals have and what diet were they designed for?
Heterodont detention for eating bugs
What do the terms Heterodont, thecodont and Diphyodont mean?
Heterodont: different types of teeth Thecodont: teeth in bone. Diphyodont: Two sets of teeth.
The advanced mammalian kidney evolved because of what selection pressures?
High energy endothermy and insect diet (high nitrogenous waste)
When did mammals first appear in the fossil record?
Jurassic period, before birds 150 mya
What sensory adaptations allowed mammals to efficiently exploit this niche?
Keen hearing, vibrissae, echolocation, microchirpterians evolved from nocturnal insectivores
How has the idea of competitive inferiority been used to explain lack of radiation of marsupials of South America compared to the adaptive radiation of those in Australia?
Land bridges brought Laurasia placental mammals in contact with marsupials
What were the three major faunistic assemblages of the cenozoic?
Laurasian - Placental South America - Mixed placental and Marsupial Australian - Marsupial