What is the tree format called where a hierarchy of relationships can be depicted?
phylogeny
T/F: In a phylogeny, twigs that grow out of the same branch share more of their history than twigs that grow out of another branch.
T
How many named species are there on the planet? How many are likely in total, named or unnamed?
2.3 million
9 million
What is known as the way an organism "makes a living" through where it lives, what it eats, and when it is active?
ecological niche
T/F More niches lead to fewer species, because the quicker natural selection can act on the available variation and select for phenotypes to fill those niches.
F - more species
What refers to the rapid diversification of a organism that fills all available niches with newly evolved species?
adaptive radiation
What is an example of adaptive radiation?
Darwin's finches: a small group of finches migrated from South America to the Galapagos 500,000 years ago. There, there were many niches to be filled. Over time, 14 different species evolved, including the ground finches, cactus-eating finches, insect-eat
Concerning adaptive radiation, how did the modern world evolve during the Cretaceous?
65 million years ago dinosaurs that dominated all niches went extinct, leaving the niches empty. A small, nocturnal ancestor diversified rapidly into mammals and natural selection resulted in phenotypes to fill all of the different niches.
Why do we care about phylogenies?
- base our naming system (taxonomy) on the ancestral relationships
- informs hypotheses about how and why species evolved particular adaptations
- comparisons of closely and distantly related species allow us to deduce the function of adaptations, using t
T/F All apes are quadrupedal.
T
How do chimps and gorillas walk? Orangutans?
Chimps and gorillas are knuckle walkers and orangutans walk on their palms (although are mostly arboreal)
What is the current hypothesis on why chimps and gorillas are knuckle walkers?
chimps and humans are more closely related to one another compared to chimps and gorillas, therefore, knuckle walking would have had to evolve independently, twice, from a non-knuckle walking ancestor
What refers to the construction of phylogenies?
systematics
How do researchers determine patterns of relationships in terms of phylogenies?
look at many different traits
Why must researchers look at many different traits to detect patterns of relationships?
individual traits may be misleading - bats are more related to mice than they are with flies. thus, you must look at traits other than flying
T/F Researchers only look at similarities between organisms to construct phylogenies.
F - the differences between organisms tell whether or not organisms are closely related to one another, along with similarities
What do researchers look at to determine phylogenies?
amino acid sequences, morphologies, behaviors
T/F We can reconstruct dinosaurs from 60 millions years ago based on their preserved DNA found in mosquitoes in tree sap amber.
F - DNA does not preserve well
What refers to a trait in which the similarity is inherited from a common ancestor?
homology
What is an example of an homolgy?
arms and legs both have an upper bone (humerus/femur) and two lower bones (ulna and radius/tibia and fibula)
What are homologous structures in birds, reptiles, and mammals?
legs
What refers to a trait in which the similarity is due to independent evolution of traits in two species?
homoplasy
T/F In homoplasy, animals diverged on similar solutions to similar problems through the process of natural selection.
F - converged
What is an example of homoplasy?
bird and insect wings - they both have similar functions, but different structures; eyes in vertebrates and cephalopods; wolf-like anatomy and behavior in mammalian wolves and marsupial Tasmanian wolves
What is another word for a homoplastic trait?
analogous trait
What are the two types of homologous traits?
ancestral and derived
What type of homologous trait refers to traits that have not changed from the beginning?
ancestral trait
What type of homologous trait refers to traits that have change from the ancestral state of the groups being classified?
derived trait
What is an example of an ancestral trait?
the five digits (pentadactyly) in the primate hand and foot
What is an example of a derived trait?
horses have a single digit, while their ancestors had three (and their ancestors had five, like all ancestors to the mammals)
T/F Ancestral versus derived status is relative.
T
T/F When making a tree, look at the ancestral shared traits.
F - derived shared traits (mammals - fur, lactation, warm-bloodedness)
What type of evolution refers to the formation of independently similar features in two or more organisms due to selection?
convergent evolution
What are the ancestors to humans, platypuses, and chickens?
reptiles
T/F Humans lost the ability to lay eggs, but chickens and platypuses retained this trait, thus the trait is derived.
F - ancestral
What is an example of an homologous trait between platypuses and humans?
lactation to young
What is an example of an analogous/homoplastic character between humans and chickens?
bipedalism
Analogous/homoplastic characters are seen in what type of evolution?
convergent
How can we tell whether a character is ancestral or derived?
- look at embryological development (ancestral traits typically are shown then)
- fossils
- phylogenetic analysis from the inclusion of so-called out-groups
What are examples of ancestral characters seen in embryos?
gills, slits, and tail
The absence of a tail in humans, and in other apes, is the ________ character.
derived
The presences of a tail is the _________ character.
ancestral
What is an example of phylogenetic analysis to determine an out-group?
looking at just monkeys and apes, monkeys have tails and apes do not. Thus, with only two groups it is not clear whether or not the tail is ancestral, but when looking at an out-group, like carnivores (dogs) or even reptiles, we can see the presence of a
What is the study of the overall physical similarities among organisms that are used in forming biological classifications?
phenetics
T/F Phenetics counts only derived traits that are shared, and also doesn't distinguish between homologous and homoplastic traits.
F - counts both ancestral and derived traits
What refers to the evolutionary relationships between organisms (derived vs ancestral homologous traits) that are used to form biological classifications?
cladistics
T/F Cladistics counts only shared derived traits, and ignores shared ancestral traits.
T
Which option, cladistics or phenetics, do scientists believe is more viable?
cladistics
Why do scientists believe cladistics is more realistic?
- if rates of evolution differ (for example, when a species moves to very different environment, or allopatric speciation occurs) then ancestral traits may be lost quickly in one lineage, making it appear distantly relation even to its closest relative
-
In terms of systematics, when two species separate, what is seen in their DNA?
more closely related species have less mutations when compared to one another, whereas, distantly related species will have accumulated more mutations differentiating them than closely related species
What refers to the phenomenon in which the genetic tree can be calibrated for time by hypothesizing that mutations occur at an approximately constant rate?
molecular clock
When constructing a molecular clock, is fossil evidence crucial?
No
Who is the closest relative (living or dead) of Homo sapiens?
chimps
How do humans greatly differ than apes?
bipedalism, large brains, symbolic language and construct complex tools
Is the evolutionary classification in which humans are in their own family more or less realistic compared to the cladistic classification in which we are considered apes
less realistic - we are apes
What term refers to all African apes?
hominid
What term refers to humans and human ancestors?
hominins
What order are humans in?
Primates
Why do we study non-human primates?
they are our closest extant (living) relatives, conservation/protection
What method looks at shared traits, including morphology, physiology, and behavior, in primates?
comparative method
What does reasoning by analogy focus on?
differences
How are primates diverse?
body size, habitat and diet, social organization, and activity patterns
T/F Natural selection shapes behavior
T
T/F Primates have a single characteristic that distinguishes them from the rest of mammals.
F - there is a suite of characters, present in varying degrees in different primate groups
What are some defining traits for primates?
- opposable toe/thumb and prehensile (grasping) hands
- nails (instead of claws) and tactile finger pads
- reduced reliance on olfaction (smell)
- less area devoted to oder detection (smaller snout)
- increased reliance on sight, eyes encased in bone and
What is the purpose of nails?
to protect the sensitive ends of digits
In terms of primates' sight, what refers to overlapping fields of vision with both sides of the brain receiving images from both eyes, allowing for detailed depth perception?
binocular stereoscopic vision
T/F Many primates do not perceive color.
F - they do perceive color and it is very useful for detecting objects in a moderate contrast environment like a forest/jungle, especially in daytime.
What is color used for in terms of primates?
selection of mates, to show mood, and to identify food
What type of primate does not have much color vision?
nocturnal (night feeding) primates because it is difficult to distinguish color in low light
T/F Increased reliance on sight allows for a decreased reliance on smell.
T
T/F Primates have enlarged, distinguished regions of their brain that are associated with learning, intelligence, motor control and coordination.
T
T/F Primates rely more extensively than other mammals on learned behaviors.
T
What, in turn, does the emphasis on learning lead to in primates growing period?
they spend a longer time growing up to maturity, both biologically and socially
T/F Learning means new behaviors cannot be passed from one generation to the next.
F - they can be taught to the next generation
What are some distinctive characteristics in primate's reproduction?
small number of offspring, long gestation, high interbirth interval, long juvenile period, and lots of parental care
T/F The mother-infant bond is not very strong in primates.
F - the bond is strong and long lasting in primates. Primate infants are helpless and depend on their mothers for their food, warmth, protection, affection, and knowledge. The mother calorically invest a ton into their young. The bond can last a lifetime.
What type of teeth do reptiles have?
all the same, they are sharp and grow throughout life - homodonts
Why are mammals heterodonts?
they have different types of teeth, and have two sets of teeth during their lifetimes: deciduous and permanent
In primates, what are the flat front teeth used for cutting, slicing, and gnawing food?
incisors
In primates, what teeth are located in front of the jaw behind the incisors, that are normally used by mammals for puncturing and defense?
canines
In primates, what teeth are in the back that are used for crushing and grinding food?
premolars
In primates, what teeth are furthest back in the jaw that are used for crushing and grinding food?
molars
T/F Humans are unique in their reduced canines.
T
What is the dental formula equation?
top I.C.PM.M./bottom I.C.PM.M
T/F In primates, the dental formula does not vary and is always 2.1.3.3.
F - it varies and 2.1.3.3. is the maximum of each
T/F The current primates dental formula is reduced from the common primate ancestor who's dental formula was 3.1.4.3./3.1.4.3.
T
What is the dental formula for humans, apes, and Old World Monkeys?
2.1.2.3./2.1.2.3.
What is the dental formula for New World Monkeys?
2.1.3.3./2.1.3.3.
T/F For Strepserrhines (primitive primates), the dental formula varies a lot.
T
Why do warm-blooded vertebrates eat more than cold-blooded vertebrates?
to regulate their temperature
The diversity of teeth allows for what in mammals?
flexibility and diversity of diet
What term refers to living on the ground?
terrestrial
What term refers to living in the trees?
arboreal
Did primates evolve to be arboreal or terrestrial?
arboreal, but several groups later descended from the trees and are adapted to terrestrial life
Where are most primates most adapted to?
tropics in forests: Central and South America, Africa, and Asia
What primates are the only ever to reach Australia and Antarctica?
humans
How many different species of primates are there in the world?
300
Using genetic and morphological data, what two large suborders can scientists split the primate order into?
strepsirrhini and haplorrhini
How long ago did primates evolve?
60-70 million years ago
Are humans haplorrhines or strepsirrhines?
haplorrhines, thus they are more closely related to monkeys and apes
What do strepsirrhines and haplorrhines differ in?
their noses
Which suborder has a wet nose?
strepsirrhine
What produces a dry nose in haplorrhines?
an upper lip that separates their nostrils from their mouth
T/F Strepsirrhines often lack one or more of the general characteristics of primates.
T - some lack color vision or have a single claw on a hand or foot
Which primate suborder relies more on smell?
strepsirrhines
Which primate suborder generally has a smaller brain relative to their body size?
strepsirrhines - still larger than other mammals, however
Where are strepsirrhines found?
Africa and Asia, mostly in Madagascar
Which suborder typically has a toothcomb?
strepsirrhines
What causes the glowing eyes in strepsirrhines?
tapetum lucidum - a reflective layer at the back of the eye that enhances night vision in nocturnal strepsirrhines
How do strepsirrhines locomote?
vertical clinging and leaping
What closed bony ring around the eye do strepsirrhines have?
post-orbital bar
How many living species are there of strepsirrhines?
22
What are the three main groups of strepsirrhines?
lorises and galagos, and lemurs
What type of strepsirrhines tend to be quite small, tree-dwelling animals that are most active at night, eating fruit, tree sap (or gum), and insects?
lorisiformes (omnivores)
Are lorises or galagos faster?
galagos - fast agile vertical clingers and leapers, springing from one branch to the next. mostly found in Africa
What do galagos mostly feed on?
tree gum
What strepsirrhines are found almost exclusively on Madagascar?
lemurs
What do lemurs eat?
diverse diets - most varied Stresirrhines
T/F Lemurs have female dominant social systems.
T
How are lemurs a classic example of an adaptive radiation?
a small colonizing population diversified into a great many different species over time, filling different ecological niches
What are the 'higher primates' known as?
haplorrhines
What consists of the haplorrhines?
tarsiers, monkeys, and hominoids (humans and apes)
In terms of the brain, what is different between haplorrhines and strepsirrhines?
the brain is larger and more complex in haplorrhines
In terms of the bones around the eyes, what is different between haplorrhines and strepsirrhines?
haplorhini have post orbital enclosures and strepsirhini have the post orbital bar
What are the two types of haplorrhines?
tarsiiformes and anthropoids
In many ways tarsiers are strepsirrhine-like, however they are more related to haplorrhines because of their what?
genetics
What makes up the anthropoids?
monkeys and apes
What do tarsiers eat?
90% insects and 10% other vertebrates = carnivores
When are most, except one, anthropoids (haplorrhines) active?
day - diurnal
T/F Anthropoids only include arboreal species.
F - terrestrial and arboreal
T/F Anthropoids are found in both the New World and Old World.
T - New World (Central and South America) and Old World (Africa and Asia)
What are New World anthropoids called?
platyrrhines - all monkeys
What are Old World anthropoids called?
Catarrhines - monkeys, apes, and humans
How do monkeys typically walk?
quadrupeds - arms and legs of similar length, keeping the spine parallel to the ground
How long ago did New World and Old World monkeys split from one another?
at least 30 millions years ago
Do NWM or OWM have a prehensile tail?
NWM - all are arboreal
What is the differences in noses between NWM and OWM?
platyrrhines (NWM) have flat noses with nostrils that face sideways while catarrhines (OWM) have downward noses with nostrils that face down
How do platyrrhines and catarrhines teeth differ?
catarrhines have one less premolar
What are old world monkeys referred to as?
cercopithecoids
Are cercopithecoids more closely related to humans or NWM?
humans - share same dental formula
Where do OWM live?
wide range of environments: rain forests to Savannahs to the snowy Japanese mountains
What do OWM eat?
mixed diet of fruits and leaves, some eat meat and kill small animals
What is the social structure of OWM?
multimale/multifemale or unimale/multifemale
What division of old world anthropoids refer to apes and humans?
hominoids
Hominoids characteristics:
no tails, specialized upper body and shoulder anatomy, generally larger body size, brain size larger relative to body size, more complex brains, greater intelligence and learning ability, invest more in young
How are hominoids dental structure different than monkeys?
hominoids have Y-5 lower molars with 5 cusps, instead of 4 - bilophodont
In terms of spinal structure, how do hominoids differ from monkeys?
more vertical (orthograde)
What does the upper body and shoulder anatomy of hominoids allow them to do?
raise their arms above their heads easily, facilitating suspensory climbing
Upper anatomical differences in hominoids than monkeys:
- larger and longer clavicle
- very flexible shoulder joint and capable of wide angle movement
- hominoid shoulder blades are located more toward the back and face outward, monkey shoulder blades are more to the sides of the chest
What refers to the ability to hang onto branches by raising its arms above the head, and to climb from this position?
suspensory climbers - brachiators (should be called ape bars, not monkey bars)
20 - 8 may there were many types of hominoids, today only a few species survive in what three major categories?
lesser apes: hylobates - gibbons and siamangs
great apes: orangutan (Pongo), gorilla (Gorilla), chimpanzee (Pan troglodytes), bonobo (Pan paniscus)
humans: (homo)
What makes up the lower apes?
gibbons and siamangs - all arboreal, eat fruit, leaves, flowers, and insects
Who are the only true brachiators, being able to swing across large gaps in forest canopy using their extraordinarily long arms?
hylobatids - lesser apes
What are hylobatids social structure like?
monogamous (pair bonded), will engage in male parental care, territorial and males and females sing coordinated vocal duets to establish and maintain their territories
What is our family?
Hominidae - the great apes
Orangutans - Pongo
Gorillas - Gorilla
Chimpanzees - Pan
Bonobos - Pan
Humans - Homo
Orangutans:
- vegetarian (60% fruit diet)
- fist walk
- solitary (Borneo and Sumatra)
Gorillas:
- forested areas of Africa (mountain versus lowland species)
- largely terrestrial
- knuckle walkers
- vegetarian (85% leaves)
- single male/multi female groups - harems
- largest living primate
Common Chimps:
Pan troglodytes
- 70% fruit diet, but will eat meat
- knuckle-walkers, but more active and agile than gorillas
- terrestrial and arboreal
- multimale/multifemale groups
- strong male social bonds, sophisticated tool use
- females leave the male-dominated
Bonobos:
Pan paniscus
- only found in rainforests of DRC
- knuckle walkers
- very little animal protein
- multimale/multifemale groups
- strong female social bonds, rather than male in chimps
T/F Humans are the only living members of the genus Homo.
T - but fossils demonstrate that there used to be other species
Where did humans evolve?
Africa
Primate taxonomy review:
Primates can be split into two large kinds: strepsirrhines, like lemurs and galagos, and haplorrhines. We are haplorrhines.
Haplorrhines can also be split into two groups, one tiny group comprised only of the tarsiers, and another large group called the a
What is the study of relationships of organisms to each other and their environment?
ecology
T/F An organism's environment includes both the physical and social stresses.
T
Why do primates eat?
source of energy and particular nutrients
What is another word for a toxin? Examples?
secondary compounds - chocolate, caffeine, nicotine
Energy consumed for breathing, keeping the heart beating, keeping your core temperature up/down is known as what?
basal metabolic rate (BMR)
T/F Basal metabolic rate and body weight are on a one-to-one scale when graphed.
F - less than one-to-one - large animals use less energy per unit of body weight than smaller animals, small animals therefore need to eat higher-quality food or need to eat more often than larger animals
What refers to additional calories needed to do more than "exist"?
active metabolism - depends on body size and activity level (for primates, usually about twice BMR) - can be triggered by growing, reproducing, thinking
Are the costs of reproducing higher in females or males?
females
What nutrients provide energy?
carbohydrates, fats/oils
What nutrient provides amino acids?
protein
What nutrient is necessary for proper regulation of metabolism, growth, etc?
vitamins/minerals
Examples of secondary compounds?
alkaloids, tannins, caffeine
What refers to the consumption of high in energy, but low in protein fruit?
frugivory
What refers to the consumption of leaves (sometimes may be toxic, but are abundant)?
folivory
What refers to the consumption of insects?
insectivory
What refers to the consumption of tree gums?
gummivory
What refers to the consumption of vertebrates?
carnivory
What refers to the consumption of a wide variety of things?
omnivore
What are dietary adaptations seen in morphology?
teeth (gain access to food, bite food into edible pieces, crush food) and gut (process food to gain nutrition, process food to avoid toxins)
What are the teeth and gut like in insectivores?
teeth: sharp cusps
gut: short, simple
What are the teeth and gut like in folivores?
teeth: small incisors, well-developed molar shearing crests
gut: large cecum, complex stomach, enlarged large intestine to break down cellulose in the plant matter
What are the teeth and gut like in fugivores?
teeth: large, broad incisors; low, flat molars
gut: long small intestine, enlarged digestive systems, but not as complex as folivores
What are the teeth and gut like in gummivores?
teeth: long incisors and canines
gut: unspecialized, but long cecum
morphology: long claws for clinging
How does the diet of a primate affect its home range?
availability of food and seasonality of food
How might group living help reduce predation on group members?
- increased detection
- increased deterrence abilities
- dilution effect
Why did terrestrial primates evolve larger body size and larger group size?
most susceptible to predation
Example of dilution effect in primates?
red colobus - when chimps around they stay close together, when nothing is around they spread out
What are some costs to group living?
disease, limited resources
What is the study of how the benefits and costs interact dependent on the ecology and social organization in primate groups?
socioecology
T/F Terrestrial primates tend to live in larger groups.
T
T/F Frugivores tend to live in larger groups than folivores.
T
T/F Diurnal species tend to live in larger groups than nocturnal species.
T
What is a solitary group? Example?
territory made up of females and their offspring isolated from other females, though many females may exist within the territory of a single male - orangutan
What is a pair-bonded group? Example?
single male, single female and their offspring occupy and defend territory - gibbons
What is a polyandry? Examples?
one female with multiple males and offspring in territory - marmosets and tamarin monkeys
What is a polygyny? Examples?
one dominant male, multiple breeding females; huge male competition, gorillas, geladas, howler monkeys
What is a polygyandry? Examples?
multiple males, multiple females - baboons, chimps
not an equal opportunity to mate
What determines the primate social group membership?
females and males distribute themselves around the females
Are reproductive strategies conscious decisions?
no
T/F In chimps and orangutans, there is very little male parental care.
T
What is the limiting resource to female's reproductive success?
access to food
What is the limiting resource to a male's reproductive success?
access to females
What are the two reproductive processes primate females invest most of their energy?
gestation and lactation
What is a caloric investment analogy to a woman's pregnancy?
same amount to run 800 miles in 9 months time
T/F Gestation is more energetically costly than lactation.
F - lactation is more energetically costly
T/F More food leads to more offspring.
T
What would happen if resources were evenly distributed?
undependable, leads to competition for reaching resources faster, not directly between individuals over access to a particular portion of the resources
What happens if resources are patchy?
defendable, creates direct competition over access to resources
What influences the female primate reproductive success?
- longevity
- group size
- rank
- sociality
In savanna baboons, why do many high maternal rank mothers have daughters?
the daughters inherit their mothers rank, while sons do not
Whereas, why do low-ranking savanna baboons overproduce sons?
they can go off and be high ranking
What refers to female's tendencies to remain in their natal group after they mature?
philopatric
What are the benefits of social baboons?
- more reproductive success
- live longer
- independent of rank
In terms of reproduction, what are a male's two investment options?
- finding new mates
- helping offspring survive
What type of sexual selection results from competition among the same sex (in primates, this is usually males), dominant males gain access to mates?
intrasexual selection
What type of sexual selection results from preferences of one sex for particular traits in another (in primates, this is usually females preferring particular male traits)?
intersexual selection
What refers to differences between males and females of the same species?
sexual dimorphism
Where is sexual dimorphism mostly seen?
mating systems that involve male-male competitions
T/F Sexual selection is often stronger than natural selection.
T
Is there more variability in male or female reproductive success?
male
Is sperm competition an example of intrasexual or intersexual selection?
intrasexual
What is the color seen in a mandrill linked to?
levels of testosterone and its fighting ability
Where is infanticide mostly seen?
single-male groups
What is a counterstrategy to infanticide?
mating with many males (paternity confusion), or aborted pregnancy
What refers to the idea that what we see in nature is not necessarily "right?
naturalistic fallacy
How is paternal care indirect in polygynous groups?
tolerant of proximity, feeding, defends group against harassment
What type of breeding refers to when males and other individuals in a group help raise young?
cooperative breeding
Where is cooperative breeding seen?
marmoset and tamarins and humans
What refers to helping one another in a way that benefits them, but at a personal cost to yourself?
altruism
Who are mutualistic behaviors vulnerable to?
cheaters
What is the problem with group-level altruistic behaviors?
natural selection operates on the level of the individual, not the group
What is the Hamilton Kin Selection theory?
individuals can pass along their genes directly and indirectly, through helping kin reproduce
What refers to the proportion of the genes in future generation that are identical to yours because they are inherited from the same ancestor?
fitness
What refers to the passing of genes you share with a relative to their offspring?
inclusive fitness
What is the process by which a behavior is favored owing to its beneficial effects on one's relative?
kin selection
What is Hamilton's rule?
the more distant the relation (r) the higher the benefit (b) to cost (c) ration required to favor the behavior
rb>c
How are kin recognized?
morphological/pheronomal similarity (phenotype matching) or proximity (imprinting)
Is kin recognition innate or learned?
learned
What are examples of kin selection in primates?
- sharing food with kin
- grooming kin
- coalition formation
How is altruism among unrelated individuals justified?
reciprocal altruism
When does reciprocal altruism seem to happen?
- frequent interactions
- cost must be less than benefit
- memory of events
- tends to occur in social animals with long lives, long memories, sophisticated cognition
What refers to the large brains in primates?
encephalization
What theory refers to the length and timing of the different parts of the life cycle?
life history theory
What refers to aging?
senescence
Why do we grow old and die?
aging is a consequence of selection favoring genes that increase one's fitness early in life at the expense of their fitness later in life
pleiotropic effects of genes that favor early fertility (testosterone)
What theory of evolution to explain brain size in primates has to do with social cues?
social intelligence
What theory of evolution to explain brain size in primates has to do with the primate's environment?
behavioral flexibility