Exam 2 Flashcards
primates
the order of mammals that has a complex of characteristics related to an initial adaption to life in the trees
parallel evolution and example
when the same trait has arisen separately in two closely related species and is not due to arisen once in a common ancestor
ex. finches in different parts of the world have evolved similar structures independently
convergent evolution and example
independent evolution of similar adaptations in rather distinct evolutionary lines
Ex) wings in bats, insects and birds
Ex) Seen in Australia and New Zealand with placentals and marsupials
homologous vs. analogous traits
Homologous – physical traits in two species that have similar structures but may or may not show a similar function
Ex. Arms and legs both have one upper bone and two lower bones
Analogous – physical traits with similar functions in two species but a different structure
Ex. Bird and insect wings have similar function (flight) but different structures
primitive traits and example
traits that have not changed from an ancestral state
Ex. Five digits in hand and foot has not changed
derived traits and example
traits that have changed from an ancestral state
Ex. Horses have single digits while ancestors had 3 or 5
Even toes: Artiodactyls
Odd toes: Perissodactyls
phenetic and example
overall physical similarities among organisms
Ex. Overall genetic distance
cladistics and example
primitive vs. derived traits, group animals together since they have shared derived traits, evolutionary relationships between organisms (derived vs. primitive traits) are used to form biological classifications
Ex. Count shared-derived traits
humans are of the ______ (animals with a spinal cord)
phylum chordata
animals with backbones, all have bilateral symmetry
sub-phylum vertebrata
all phylum chordata possess _____ at some point (a flexible internal rod that runs along the back of an animal)
notochord
when did mammals arise?
~200 mya
what sets mammals apart from other vertebrates/
they usually give birth to live offspring rather than eggs
3 types of mammals
Marsupials (kangaroos, give birth to premature offspring and keep in pouch)
Monotremes (platypus, lay eggs)
Placental (humans, limits # of offspring)
K-selection and example
produce few offspring and invest a lot into maximizing each offspring’s chances
Ex. Primates
R-selection
produces huge number of offspring and provide little care
Ex. Fish, frogs, insects
childcare for chimps vs. humans
chimps:
- take a long time to produce offspring
humans:
- don’t wait until child iis mature to have another
homiotherms
Mammals are this;
Capable of maintaining a constant body temp under most conditions
3 ways mammals maintain homeostatis
furr insulation
vasodilation (increases heat loss, increases blood flow)
vasoconstriction (reduces heat loss, reduces blood flow)
4 types of teeth
incisors - flat front teeth used for cutting
canines - located in front, used for puncturing and defense
premolars - back teeth, crunching and grinding food
molars- furthest back, crunching and grinding food
dental formula and what do humans have
incisors: canines: premolars: molars
Humans: 2:1:2:3
allows for wide range of diet
mandible vs maxillae
mandible - lower jaw
maxillae - upper jaw
medulla oblongata
part of the hindbrain with pons and cerebellum
helps blood flow
regulates heartbeat and breathing
accounts for opiates causing trouble with breathing
pons
part of hindbrain with medulla and cerebellum
aka reticular formation
relay station carries signals from various parts coordinates body movement
involved in sleep and arousal
midbrain helps us with
vision
forebrain
chemical sensing/smell
involves thalamus (all sensory output goes through here) and hypothalamus (makes hormones)
primates vs. mammals vs. reptiles brain
p - large brains, esp. in visual aspect
m - large forebrain responsible for sensory info
r - large mid and hind brain, rely on vision and hearing
grasping hands
five digits on each hand
primitive trait for mammals
prehensile
capable of grasping with toes/feet
humans have lost this due to bipedalism
terrestrial vs. arboreal
t - living on the ground
a - living in trees (need grasping!)
primates are arboreal but several have switched to terrestrial
generalized vs. specific structures and examples
Gen – biological structures adapted to a wide range of conditions and used in very general ways
Ex. Gen limb structure is very flexible
Spec – narrowed down possible rate of uses
Ex. Horses single digit hooves are very specialized for running quickly
binocular stereoscopic vision
overlapping fields of vision, allows for depth reception
necessary adaption for life in the trees and judging distances when jumping
stereoscopic vision and color
color - useful for identifying objects in a moderate contrast environment
nocturnal primates do not have much color vision
thought early ancestors were ____ and ________
arboreal and nocturnal
color vision and living on ground/bipedalism came after
primates rely more extensively than other mammals on _______ __________, which means that they can be passed on from one _____ to the next
learned behaviors; generation
prosimians
biologically primitive primates (all strep. and tarsier) compared with anthropoids
anthropoidea (anthropoids)
the suborder of primates consisting of monkeys, apes and humans
strepsirrhini characteristics
often lack one or more primate characteristics
rely more on smell
brains are smaller relative to body size
many are nocturnal
variable in body size and social group size
all found in old world (african, asia and europe)
types of strepsirrhini
lorises - nocturnal, moist nose for sense of smell
lemurs - only found in madagascar, vary in body size, diet, and diurnal
haplorrhine
higher primates, consisting of monkeys and hominids (humans and apes)
rely on visual abilities and more complex social structure
almost all are diurnal
suborders of haplorrhine
tarsiiformes
platyrrhini
monkeys vs. apes and humans
m:
-tails
-smaller brains relative to body size
-spine parallel to ground
-quadruped with equal length limbs
a+h:
-no tails
-larger size
-greater intelligence
-spend more time raising young
-Y-5 molar cusp
NWM vs. OWM and examples
NWM:
-sexually dimorphic
-live in mix sex groups, but female outnumber male
-eat fruit
ex) howler monkey
OWM:
-eat fruit, leaves and small animals
-sexually dimorphic
ex) baboons
Gibbons (how they behave, interact with one another, where they are found, and what they eat)
- no sexual dimorphism
- monogamous and mate for life, no dominance
- Tropical rain forests in SE Asia (thailand, vietnam, burma, malay peninsula, etc.)
- eat fruit and sometimes leaves
- group of only adult male, female and offspring
- defend territory with loud vocalizations