Chapter 6

tooth comb

anterior teeth (incisors and canines) that have been tilted forward creating a scraper

preadaptation

an organism's use of an anatomical feature in a way unrelated to the feature's original function vertical tendency in a prehuman ancestor was an essential preadaptation to humans' bipedality

primate parenting

fertility; birth to relatively few offspring at a time, commonly just one birth interval; relatively long period between births preadult care: elongated and intensive

dermal ridges

fine ridges on the inside surfaces of fingers and toes that further enhance the tacticle sense and they increase the amount of friction when grasping an object

hylobatids

gibbons

pongids

great apes

anthropoids

higher primates, monkeys, apes and humans fall into two infraorders platyrrhines (new world) and catarrhines (old world)

canine-premolar honing complex

the dental form in which the upper canines are sharpened against the lower third premolarswhen the jaws are opened and closed slices food and other plants

phylogeny

the evolutionary relationships of a group of organisms based on shared characteristics, including physical traits, genetics and behavior

rhinarium

the naked surface around the nostrils typically wet in mammals, primates have lost this and long snout and sense of smell

dental formula

the numerical description of a species' teeth, listing the number in one quadrant of the jaws, of incisors, canines, premolars and molars; primates have decreased in number

olfactory bulb

the portion of the anterior brain that detects odors smaller in primates

parental investment

the time and energy parents expend for their offspring's benefit

dietary flexibility of primates

through multiple tooth types and reduced number of teeth

sectorial (premolar)

refers to a premolar adapted for cutting

bilophodont

refers to lower molars, in old world monkeys that have two ridges

diurnal

refers to those organisms that normally are awake and active during daylight hours in primates evolved due to depth perception and color vision

platyrrhine nostrils

round and separated by a wide nasal septum

prosimians

sometimes called lower, primates are the most primitive and retained large number of ancestral traits

ceboids

superfamily of platyrrhines, cebids and atelids are widespread in latin america spend all their time in trees

Sir Wilfred E. Le Gros Clark

(1895-1971) identified 3 prominent tendencies in primates; arboreal adaptation, dietary plasticity and parental investment

dietary plasticity

a diet's flexibility in adapting to a given environment

precision grip

a precise grip in which the tips of the fingers and thumbs come together enabling fine manipulation

diastema

a space between two teeth

arboreal adaptation

a suite of physical traits that enable an organism to live in trees

prehensile tail

a tail that acts as a kind of a hand for support in trees, common in new world monkeys

loph

an enamel ridge connecting the cusps on a tooth's surface

versatile skeletal structure

bones making up shoulders, limbs, hands, and feet tend to be separate and are articulated at highly mobile joints

primitive characteristics

characteristics present in multiple species of a group, such as the rhinarium

derived characteristics

characteristics present in only one or a few species of a group, ex. living lemurs' tooth comb

catarrhine nostrils

close together and point downward

power grip

defined by john napier a fistlike grip in which the fingers and thumbs wrap around an object in opposite directions

Y-5 molar

hominoid's pattern of lower molar cusps

hominids

humans

hominin

humans and human ancestors in a more recent evolutionary taxonomy; based on genetics

genetic classification

hylobatids, hominids (great apes and humans) includes pongines (orangutans), gorillines (gorillas), and hominines (chimps, bonobos, and humans) hominines are divided into panins and hominins

anatomical classification

hylobatids, pongids, hominids

opposable thumb

it can touch each of the four fingertips, enabling a grasping ability

Thomas Huxley

man's place in nature treatise on primate anatomy and human evolution

primates

monkeys and humans, share a common feature like forward facing eyes, common ancestry, able to live anywhere (adapt),

primate adaptation in microcosm

primates have a generalized skeletal structure enhanced sense of touch have an enhanced sense of vision reduced sense of smell dietary plasticity

cercopithecoids

old world monkeys, two subfamilies,colobines and cercopithecines

halluxes

opposable big toes human lack in order to walk or run

brachiators

organisms that move by brachiation or arm swinging