What is a cline?

A gradual change in a phenotypic characteristic from one population to the next.

What does it mean that biological traits follow a geographic continuum?

Traits gradually change across populations rather than having strict boundaries.

What is an example of a cline from the review?

Skin pigmentation or Type B blood.

What is the prenatal stage?

The stage before birth; it includes 3 trimesters and lasts 9+ months.

What happens during the postnatal stage?

Neonatal, infancy, childhood, juvenile, puberty, and adolescence occur after birth.

What is the neonatal period?

The first month after birth.

What is infancy?

The period beginning around the second month and associated with weaning, rapid growth, motor skills, and cognitive development.

What happens during childhood?

Childhood occurs approximately from ages 3–7.

What is the juvenile period?

Approximately ages 7–12.

What is adolescence?

The period after puberty.

What happens during the adult stage?

The reproductive period and eventually senescence.

What is growth velocity?

The rate of growth per year.

What is senescence?

Biological changes in later adulthood that include a reduction in homeostasis.

What is menopause?

Loss of ovarian function.

Why are humans different in reproductive senescence?

Reproductive senescence is very rare in nonhuman primates, while humans experience menopause.

What is deciduous dentition?

The first set of teeth associated with infancy and childhood.

What is permanent dentition?

The adult set of teeth that replaces deciduous teeth.

What is sexual dimorphism?

Differences in physical characteristics between males and females.

What is an epiphysis?

The end portion of a long bone.

What is a diaphysis?

The shaft of a long bone.

What is the growth plate?

The area associated with growth of a long bone.

What happens to body mass as temperature decreases according to Bergmann's Rule?

Body mass tends to increase as temperature decreases.

Why are larger, rounder bodies advantageous in cold environments?

They help retain heat.

What happens to appendages as temperature increases according to Allen's Rule?

Appendages tend to increase in size.

What is the main idea of Bergmann's Rule?

Colder environments are associated with larger, rounder body forms.

What is the main idea of Allen's Rule?

Warm environments are associated with larger appendages.

What does UV radiation help synthesize?

Vitamin D.

Why is vitamin D important?

It is necessary for proper skeletal development.

What can inadequate vitamin D contribute to?

Rickets and osteomalacia.

What does UV radiation deplete?

Folic acid.

Why is folic acid important?

It is necessary for DNA synthesis and spinal development.

What is melanin?

A chemical substance in skin that screens out UV radiation from the sun.

What happens to pigmentation with greater sun exposure?

Skin pigmentation tends to be darker.

Why can darker skin be advantageous in high-UV environments?

It provides greater protection from UV damage.

Why can lighter skin be advantageous in lower-UV environments?

It allows more UV penetration for vitamin D synthesis.

What is the tradeoff involved in skin color?

Skin needs to be light enough to allow adequate UV penetration for vitamin D but dark enough to protect from sun damage.

What are osteoblasts?

Bone-forming cells that synthesize and deposit bone and secrete osteoid.

What are osteoclasts?

Bone-resorbing cells that remove bone tissue.

What are osteocytes?

Mature bone cells involved in bone maintenance.

What is Wolff's Law?

Bone responds, adapts, and remodels in response to external biomechanical pressures and needs.

What happens to bone with use according to Wolff's Law?

Bone increases in size.

What happens to bone with disuse according to Wolff's Law?

Bone atrophies and stops maintaining its shape.

Where is the frontal bone?

On the front of the skull/forehead.

Where is the parietal bone?

On the top and sides of the skull.

Where is the occipital bone?

At the back of the skull.

Where is the temporal bone?

On the side of the skull near the ears.

Where is the maxilla?

The upper jaw and a large portion of the face.

Where is the hyoid?

In the neck.

Where is the femur?

In the thigh.

Where is the tibia?

In the lower leg.

Where is the humerus?

In the upper arm.

Where is the radius?

In the forearm.

Where is the ulna?

In the forearm.

Where is the scapula?

The shoulder blade.

Where are the phalanges?

In the fingers and toes.

What is a generalized primate body plan?

A body plan shared by primates that includes traits such as grasping hands and specialized vision.

Are primates typically quadrupeds?

Yes, primates are typically quadrupedal.

What type of hands do primates have?

Grasping hands with opposable thumbs and/or big toes.

What type of nails do most primates have?

Flattened nails instead of claws.

What is special about primate eyes?

They are forward-facing and provide stereoscopic vision and depth perception.

Why are forward-facing eyes useful?

They provide overlapping fields of view and 3-D depth perception.

What is the primary sense in primates?

Vision.

What are the two major primate groups?

Strepsirrhines and haplorhines.

What does Strepsirrhine refer to?

A group of primates including lemurs, lorises, and galagos.

Who are strepsirrhines?

Lemurs, lorises, and galagos.

What does "wet-nose primates" refer to?

Strepsirrhines.

What is a rhinarium?

The wet nose characteristic of strepsirrhines.

Are many strepsirrhines nocturnal?

Yes.

What type of vision do strepsirrhines generally have?

Poorer color vision.

What is a tooth comb?

A specialized dental structure found in strepsirrhines.

How many teeth do strepsirrhines have according to the review?

36 teeth, with an extra premolar; dental formula 2-1-3-3.

What sense do strepsirrhines rely on more heavily?

Smell.

What is a grooming claw?

A specialized claw used in grooming, found in many strepsirrhines.

What is the tapetum lucidum?

A structure in the eye associated with low-light vision in strepsirrhines.

What does Haplorhine refer to?

The group including tarsiers, New World monkeys, Old World monkeys, apes, and humans.

What does "dry-nosed primates" refer to?

Haplorhines.

Do haplorhines have a rhinarium?

No.

How do haplorhine brains and bodies compare with strepsirrhines?

Haplorhines generally have larger bodies and brains.

What is the dominant sense in haplorhines?

Vision.

What type of vision do haplorhines have?

Binocular, stereoscopic, and color vision.

Do haplorhines have a tooth comb?

No.

Are most haplorhines diurnal?

Yes, although tarsiers are nocturnal.

What are tarsiers?

Small, nocturnal insect-eating haplorhines that live in Asia.

How do tarsiers move?

They are vertical clingers and leapers.

What is Platyrrhini?

A term meaning "flat nose" that refers to New World monkeys.

Who are platyrrhines?

New World monkeys.

Where do platyrrhines live?

Central and South America.

What are platyrrhine noses like?

Broad or flat.

What is the dental formula of platyrrhines?

2/1/3/3.

Do some platyrrhines have prehensile tails?

Yes.

What type of habitat do platyrrhines commonly use?

Arboreal environments.

What is Catarrhini?

A group including Old World monkeys and apes/humans.

What does Catarrhini refer to anatomically?

Primates with downward-facing nostrils that are close together.

Where do Old World monkeys live?

Africa and Asia.

What are catarrhine characteristics?

Downward-facing nostrils, greater body-size variation, and more sexual dimorphism.

What are bilophodont molars?

Molars with ridges joining the cusps on the inner and outer edges, forming two transverse ridges.

Which primates have bilophodont molars?

Old World monkeys.

What are hominoids?

Apes and humans.

What are major characteristics of hominoids?

Larger brains, larger bodies, broad chests, shorter trunks, no tail, and suspensory shoulders.

What type of molar do hominoids have?

Y-5 molars.

What is a sagittal crest?

A ridge of bone associated with some hominoids, including orangutans and gorillas.

Who are the Hominidae?

Orangutans, gorillas, chimpanzees, bonobos, humans, and immediate ancestors.

What is brachiation?

Moving through trees using the arms.

Which primate is especially adapted for brachiation?

Gibbons.

What are gibbons like?

Small-bodied apes from Indonesia that are arboreal, brachiating, very vocal, and socially monogamous.

What are orangutans like?

Asian, frugivorous apes with large sexual dimorphism, sagittal crests, and quadrumanual locomotion.

Where do gorillas live?

Tropical Africa, including lowland and mountainous areas.

What are gorillas known for?

Being the largest primates and having extreme sexual dimorphism.

What is gorilla social organization like?

Groups can include one or more males and multiple females.

What are chimpanzee social groups like?

Multi-male, multi-female and male dominated.

What do chimpanzee males do?

Patrol and defend territory and sometimes hunt in coalitions.

What is distinctive about bonobo societies?

Strong female bonds and coalitions can prevent male domination.

What happens to female bonobos as young adults?

They emigrate from their birth communities.

What happens to male bonobos?

They remain in their birth communities.

What is phylogenetics?

The field concerned with determining evolutionary relationships between species.

What is a phylogenetic tree?

A tree-like diagram showing how closely or distantly species are related.

What evidence can be used to create phylogenetic relationships?

Observable traits or DNA.

What is a solitary primate society?

Females occupy individual territories with dependent offspring while male territories overlap several female territories.

What is monogamy?

One male and one female live in a pair bond for an extended period.

Is monogamy always strict reproductive monogamy?

No.

What is polygyny?

One male defends several reproductively mature females.

What primate is an example of polygyny?

Gorillas.

What is polyandry?

One female has multiple males.

Is polyandry common in primates?

No, it is rare and poorly understood.

Which primates are associated with polyandry?

Marmosets and tamarins.

Why might males compete for females?

To gain priority access to reproductive females.

What can male competition select for?

Larger body size, larger canines, and loud vocalizations in some territorial primates.

What is a female reproductive strategy?

Acquiring resources for raising young, often while competing with other females.

What is the result of female rank differences?

Higher-ranked females generally provide more resources than lower-ranked females.

What is a dominance hierarchy?

A ranking of individuals relative to one another in a primate society.

What is altruism?

Helping one individual at the expense of another.

What is kin selection?

Helping relatives in ways that can increase reproductive success; associated with William Hamilton.

What is mutualism?

A relationship where individuals help each other.

Why do primates live in groups?

Group living can provide access to mates, food, and protection.

How does group living help against predators?

There are more individuals watching the surroundings and warning others.

What are the costs of living in groups?

Competition for mates and food, energy expenditure, and sometimes aggression.

How does group living help with finding food?

Other group members can help locate food.

What is social learning?

Learning behaviors from other members of a social group.

What three things help identify primate culture?

Behavior varies between groups, spreads through a social group, and endures over time.

What is tool use in primates?

Using objects to accomplish a task; it is part of the broader study of learned primate behavior and culture.

What are vocalizations?

Sounds produced by primates that can have important meanings.

What are chacma baboon vocalizations an example of?

Different grunts can communicate different meanings, including threats or reassurance.

What do howler monkey long calls do?

Establish territory and can help estimate group size.

What are alarm calls?

Calls that warn group members about predators or other dangers.

Can primates have different alarm calls for different predators?

Yes.

What is an example of different alarm calls?

Separate calls for an eagle versus a leopard.

Can primates understand alarm calls from other species?

Yes, according to the review.

What is gestural communication?

Communication using physical gestures.

What is a hand clasp?

An example of gestural communication.

What are cultural variants?

Behavioral differences that can occur between groups.

What are vocal dialects?

Differences in vocal communication between groups.

What are ape language studies?

Studies examining whether apes can communicate using systems such as ASL or symbols.

Which ape is associated with ASL in the review?

Koko.

Which ape is also listed in the review in relation to ape communication?

Kanzi.

Bergmann's Rule vs. Allen's Rule

Bergmann's Rule: body mass tends to increase as temperature decreases. Allen's Rule: appendages tend to increase in size as temperature increases.

Bergmann's Rule

Colder environments are associated with larger, rounder bodies, which help retain heat.

Allen's Rule

Warm environments are associated with larger/longer appendages, while cold environments are associated with smaller/shorter appendages.

Osteoblasts vs. osteoclasts

Osteoblasts build/form bone. Osteoclasts remove/resorb bone.

Osteoblasts

Bone-forming cells that synthesize and deposit bone.

Osteoclasts

Bone-resorbing cells that remove bone tissue.

Epiphysis vs. diaphysis

Epiphysis is the end of a long bone. Diaphysis is the shaft of a long bone.

Epiphysis

The end portion of a long bone.

Diaphysis

The shaft of a long bone.

Strepsirrhines vs. haplorhines

Strepsirrhines include lemurs, lorises, and galagos and are wet-nosed primates. Haplorhines include tarsiers, monkeys, apes, and humans and are dry-nosed primates.

Strepsirrhines

Lemurs, lorises, and galagos; generally have a rhinarium, rely more on smell, often have large eyes and a tooth comb, and many are nocturnal.

Haplorhines

Tarsiers, New World monkeys, Old World monkeys, apes, and humans; lack a rhinarium, rely heavily on vision, have color vision, and most are diurnal.

Platyrrhines vs. catarrhines

Platyrrhines are New World monkeys with broad/flat noses that live in Central and South America. Catarrhines include Old World monkeys, apes, and humans and have downward-facing nostrils.

Platyrrhines

New World monkeys; live in Central and South America; generally have broad noses and some have prehensile tails.

Catarrhines

Old World monkeys, apes, and humans; primarily associated with Africa and Asia; have downward-facing nostrils that are close together.

Hominoids vs. hominids

Hominoids are apes and humans. Hominids are orangutans, gorillas, chimpanzees, bonobos, humans, and immediate ancestors.

Hominoids

Apes and humans; generally have larger brains, broad chests, shorter trunks, no tail, and suspensory shoulders.

Hominids

The group including orangutans, gorillas, chimpanzees, bonobos, humans, and immediate ancestors.

Gibbons

Small-bodied apes that are arboreal, adapted for brachiation, very vocal, and socially monogamous.

Orangutans

Asian apes that are frugivorous, strongly sexually dimorphic, and use quadrumanual locomotion.

Gorillas

The largest primates; have extreme sexual dimorphism and generally live in groups with one or more males and multiple females.

Chimpanzees

Live in multi-male, multi-female groups; males dominate, defend territory, and sometimes hunt in coalitions.

Bonobos

Have strong female bonds and female coalitions; males remain in their birth communities while females generally leave.

Solitary society

Females occupy individual territories with dependent offspring, while male territories overlap several female territories.

Monogamy

One male and one female live in a pair bond for an extended period.

Polygyny

One male has several reproductively mature females; gorillas are an example.

Polyandry

One female has multiple males; rare in primates and associated with marmosets and tamarins.

Altruism

Helping another individual at a cost to yourself.

Kin selection

Helping relatives in ways that can increase reproductive success.

Mutualism

A relationship where individuals help each other.

Altruism vs. kin selection

Altruism is helping another at a cost to yourself; kin selection explains why helping relatives can increase the survival of shared genes.

Social learning vs. culture

Social learning is learning behaviors from other members of a group. Culture involves behaviors that vary between groups, spread socially, and persist over time.

Social learning

Learning behaviors from other members of a social group.

Primate culture

Behavior that varies between groups, spreads through a social group, and endures over time.

Vocalizations vs. alarm calls

Vocalizations are sounds that communicate information; alarm calls specifically warn group members about predators or danger.

Vocalizations

Primate sounds that can have specific meanings, such as grunts or long calls.

Alarm calls

Calls used to warn group members about predators or other dangers.

Phylogenetic tree

A tree-like diagram showing evolutionary relationships and how closely or distantly species are related.

What does a phylogenetic tree show?

It shows evolutionary relationships between species or groups and their relative relatedness.