Primate Ecology Part I

7/31/2019 Primate Ecology Part I

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Ecosystems1) Feedback system involving interrelated parts which function to

maintain themselves in a steady state, or equilibriuma. A portion of the output of the system is used as the input of

the system

b. Control of temperature in warm-blooded animals sensorysystem is the skin, hippocampus is triggered, and panting orsweating works to decrease body temperature throughrelease of body heat

c. Requirements of all systemsi. All systems must have a source of energy (in many

ecosystems, this is the sun)ii. Must have a means of transforming this into usable

forms, loss of energy at each level energytransformation

iii. Must have a built-in ability to vary with conditions in

order to return to equilibrium (allows for reactions toperturbations to the system, can react to differentlevels of stress), some trial and error as it returns tosteady state, dynamic equilibrium

iv. Inherent limits, exceeding these limits will lead to abreak-down in the system

d. Ecosystem is an open system composed of many partsworking cooperatively, and a steady state will be conservedif the parts continue to work in harmony despiteperturbation

i. Never have perfect equilibrium, always responding to

perturbations, always attempting to return toequilibrium, otherwise the system will break down

ii. Stability is the end product of millennia of partscompeting against one another to reach equilibrium

e. Ecosystem is a model of a self-regulating system2) Components of an Ecosystem

a. Biotic - livingb. Abiotic non-living (solar energy, oxygen, carbon, hydrogen,

nitrogen, phosphorus, and potassium), energy is passedthrough the ecosystem through the trophic system

i. Autotrophic plants (photosynthesizers), get energy

directly from the sunii. Heterotrophic animals (primary consumers,

secondary consumers, scavengers, parasites,decomposers), loss of energy at each level, chemicalare recycled by the system

1. Primary consumers expend a great deal lessenergy to obtain nutrition than secondaryconsumers (Eltonian Pyramid illustrates


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decreasing total biomass, and usually density,at each successive level)

a. Only 3% of the total energy available fromthe sun is incorporated into the system,only 10% of the remaining energy is

captured by the next level, if any levelbecame 100% efficient, the level belowwould be eliminated, and the top levelwould follow

b. 14 wolves studied, ate 70 herbivores inone year, each wolf weighedapproximately 70 lbs, each herbivore thatwas eaten was approximately 1000 lbs,they ate 6,000,000 lbs of plants

c. A limit being placed on any one level willlead to limitations of subsequently higher

levelsc. Food Chain the sequence of events by which energy

moves up the tropic level, from plants to herbivores tocarnivores to top predator

d. Food Web much more complex system of interactionswherein a single element may play a role at many tropiclevels

Trophic Interactions1) Biomes ecosystems can be split into six primary biomes (desert,

grassland, tropical forest, deciduous forest, taiga, tundra)

a. The first three biomes are found primarily within 20 degreesof the equator, high annual temperature, daily temperaturevariation is greater than seasonal variation, amount ofrainfall differs

b. Desert succulents and cacti, bloom during a short periodright after rainfall which is infrequent, tends to occur inbursts, most plants and animals are small, mammals andbirds are rare (difficult to maintain constant bodytemperature), difficult to maintain water, non-humanprimates do exist on the fringes (baboons, patas monkeys,some lemurs), no apes nor New World monkeys

c. Grassland exists nears the tropics as well as outside,intermittent and erratic rainfall, 10-40 inches per year, morespecies in terrestrial habitats than in any other biome, manyprimates are specially adapted (gelada baboon, patasmonkeys, ring-tailed lemurs, macaques, gorillas andchimpanzees), but no New World monkeys

d. Tropical Forest torrential rainfall, may have very short dryseason, growth is year-round (perennial), most diverse


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habitat for plants, rarely have a single dominant species,Central Africa, South and Southeast Asia, Central and SouthAmerica (Amazon), being reduced rapidly, usuallycontinuous canopy, may have multiple layers, usually cutsoff rain and sunlight from ground level, high shade tolerance

in many plants, many microhabitats for animals, specificadaptations, most primates evolved in tropical rainforestse. Deciduous Forest most abundant found outside of the

tropics, cold winters and warm summers, seasonaltemperatures vary more than seasonal, 30-40 inches of rain,seasonal, growing season is discontinuous, trees are fartherapart, fewer species represented, many primate species,cold deciduous forests of China and Japan are the furthestfrom the equators (macaques and langurs)

f. Taiga and Tundra found at the far northern latitudes, noprimates occur in these biomes

2) Given certain characteristics and environmental conditions, wecan predict which of these habitat types will dominate

a. Abiotic components are fairly constant in any areab. In similar habitats, structure and physiology of plants and

animals may be similar, but taxonomically separatec. Climax community is achieved through the process of

successioni. Ordinary change from one community to the next until

it reaches a predictable equilibrium point, distinctstages

1. Grassland to shrubs to pine forest to hardwood

forest (maples, birch, and hemlock)2. Animal communities will change in conjunction

with the plant community succession3. Natural succession is mimicked by human

induced changes, some species are speciallyadapted to this first stage of succession

ii. Occurs because each species alters the environmentin such a way that it will no longer be able to succeedas well as another species, more shade-tolerance insubsequent seedlings

1. Climax community replaces individuals of the

same species, death rate equals germinationsuccess rate, equilibrium is reached at this level

2. Disruption will lead to a reversion back to earlystages

iii. Man is keeping much of the earths surface in a stateof disclimax, where there should be grassland, wehave desert, and where we should have forest, wehave grassland by over-utilizing resources and


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altering chemical concentrations3) Leibigs Law of the Minimum the material (chemical, water, heat,

space) which is most limited in supply will be the factor limiting aspecies population size and distribution, an organism is nostronger than the weakest like in the ecological chain of materials

a. Carrying capacity of an environment depends on theselimitations4) Shelfords Law of Tolerance not only a minimum of some factor

can limit a population, but also a maximum of a factor (heat, light,water)

a. Stenothermal a population with a narrow tolerance fortemperature, more specialized, may have greater efficiencyat expense of adaptability, do not thrive is variableenvironments

b. Eurythermal a population with a wide tolerance fortemperature, more generalized

5) Interactions at different trophic levelsa. Neutralism two species do not effect each other (0,0)b. Competition each population is adversely effected (-,-)c. Mutualism the growth and survival are dependent on theother (+,+)d. Protocooperation both populations benefit, butrelationship is not obligatory (+,+)e. Commensalism one species benefits while the other isunaffectedf. Ammensalism one species in inhibited while another isnot helped directly (0,-)

g. Parasitism one species benefits by directly hurtinganother (+,-)h. Predation one species feeds directly on another species(+,-)

Interactions Among Animals1) Different Trophic Levels (Predator-Prey)

a. In a stable ecosystem, predator and prey populations are inequilibrium, if predator overkills or if prey gets too good atescaping predation, could lead to the extinction of both

b. Usually not the limiting factor for prey populations, normally

limited by food resources, though predators may be limitedby prey

i. Lemming migration diminishes through suicide, thepredator population fluctuates in response

c. Prey develop methods of escaping predators, preventspredators from overeating, coevolution may occur as mutualadaptations aid both the predator and the prey in theirarms race


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i. Detection prey must know that a predator is there,once they are detected, predator may move on to newprey, energetically most efficient for both predatorand prey

ii. Escape didnt detect them in time, means of escape,

energetic loss for both predator and preyiii. Defense after pursuitd. Three operational mechanisms for reducing predation

i. Exploiting the limits of a predators motor or sensorycapacities

1. Dispersal outrun, outfly, or outmaneuver,active

a. Patas monkey is fastest primate, male isalways on the lookout, when predator isspotted, performs ritualized display toattract attention away from the females

and young, then outrun2. Camouflage blend into surroundings, passive

a. Patas females and infants blend into thetall grasses of their environment

ii. Exploiting the limits of a predators learning abilities1. Imitate species that a predator is disinclined to

eat (mimicry), leaves or toxic animals2. Intimidate using large canines or other defense

mechanisma. Primates with large canines will yawn

upon seeing a predator to scare them off

3. Mobbing by a large group of small animalsa. Lemurs, Macaque

iii. Direct protection against predators1. Passive poison or toxins

a. Lorises smell bad because they are toxic2. Active spines, grouping behavior, vertebral

spinesa. Prey species would defend themselves

against predators that were smaller thanthree times their own mass

b. All diurnal primates are group-living

species, apparently in response topredators

3. Combination a. Small nocturnal prosimians tend to be

solitary, cryptic, quietb. Lorises develop camouflage, scapular

shield because of their slow movinglifestyle


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2) Same Trophic Levela. Competition

i. Gauses Law of the Struggle for Existence, placed twospecies of paramecium (P. aurelia and P. caudatum) ina petri dish with fixed food resources, one species

grew at the expense of the other, no direct attack,one was a better competitor (utilized resources andreproduced most quickly)

1. No two species can coexist in the sameenvironment if they have a resource in commonthat is in limited supply

2. Misinterpretation: no two closely related speciescan coexist in the same niche

ii. When a different species (P. bursaria) was added to P.caudatum, the two species reached an equilibrium,occupied different parts of the environment, not

sharing the same limiting factor1. Habitat selection one species lived on the flat

surface while the other lived on the rim2. Niche Definitions

a. Everything an animal does (functional orbehavioral)

b. Where an animal does the things they doc. Quantitative value of the measurements

of the resources available versus theresources that a particular species uses,percentage of time spent in a given part

of the habitat, overlap at each of theseparameters, unused niches

i. Among 8 South American primatespecies, dietary overlap rangedfrom 24 to 97%, cant use limitedresources, but can use otherresources

ii. Populations must shift (withinenvironment or in size) if limitingresource is being competed for

iii. Surviving in the same ecosystem

1. When resources are not limited, more resourcesthan animals needed, manage their populationsthrough epideictic factors such as fecundity,balance with the environment (more offspring ingood environment)

2. Severe climate keeps population densities low,widely dispersed so that individual will haveenough resources


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3. Differential habitat use, forest strata, adapted todifferent resources

iv. Character Displacement determine if characteristicsdeveloped because of interaction or were they pre-adapted

b. Coevolution evolution of two or more taxa that have aclose ecological relationship in which reciprocal selectivepressures operate to make the evolution of each taxonpartially dependent upon that of the other

i. Plants and animals coevolve in a similar manner aspredator-prey relationships, plants may protectthemselves by thorns, corky bark, hard seed coats,they may also evolve behaviorally, different floweringtimes, poisonous secondary compounds

1. Arms race between the coevolving speciesthrough detoxification of secondary compounds,

other alterations to the digestive tract to enableuse of these resources, exploit these protectivemechanisms

2. Plants use animals to pollinate other membersof the species, this also leads to coevolution,most of these animals can fly, looserrelationships exist with seed dispersers to moveseeds outside the seed shadow

a. Birds, bats, and primates are the primaryseed dispersers in rainforestenvironments

3. Diffuse coevolution no a one-to-onerelationship between plant and animal, butoccurs between a community of plant andanimal species

Primate Taxonomy1) Taxonomy classification based on the Linnean Hierarchy

a. Kingdom (Animalia), Phylum (Chordata), Class (Mammalia),Order (Primates), Family (idae), Subfamily (inae), Genus,Species

b. The natural scale is an inaccurate representation of theevolutionary process, prosimians and humans have been

evolving for the same amount of timec. Tree shrews are good representations of the animals that

eventually evolved into the modern primatesd. Prosimii

i. Lemuriformes Madagascar, these may have existedelsewhere, but were outcompeted by primates inother parts of the world

1. Lemuridae - diurnal, monkey-like, most are


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primarily arboreal, but ring-tailed lemurs areterrestrial adapted, walk bipedally

2. Lepilemuridae nocturnal, folivores3. Cheirogaliidae most similar to primitive

primates, nocturnal frugivores

4. Indriidae vertical clingers and leapers,folivorous, two diurnal, one nocturnal species5. Daubentoniidae hard fruit and insects in bark,

previously thought to be a rat (Aye-aye)ii. Lorisiformes

1. Lorisidae solitary but social, nest and interact,except when hunting

a. Lorisinae slow-moving, look likenocturnal lemurs, frugivorous, no tail,cryptic, Africa and Asia

b. Galaginae (galagos) nocturnal, fast-

moving, fruits and insects, long tails andlarge ears, Africa

iii. Tarsiiformes only found in Asia, only primate 100%faunivorous, nocturnal

iv. Platyrrini (New World Monkeys) only primates withprehensile tails, though only some have it, flat-nosed

1. Callitrichidaea. Callitrichidae tamarins and marmosets,

small, readapted claws instead of nails(17-21 species), gum-feeding, may causeinjuries themselves, marmosets are more

adapted to gnawing into trees, communalbreeders, all members care for young

2. Cebidaea. Cebinae monkey-like, capuchin, squirrel

monkeys, omnivore, lives in large groups,diurnal, some have prehensile tails

b. Aotinae Aodis (only nocturnalAnthropoid)

3. Atelidaea. Atelinae spider monkeys, long arms and

legs, prehensile tails, suspensory

locomotion, frugovores, cannot walkquadrupedally well

b. Alouattinae howler monkeys, foliverous,slower, prehensile tails, but notsuspensory, quadrupedal, spend a lot oftime resting

c. Pitheciinae sake and wooly monkeys,seed-predators, some have dichromatism


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like prosimiansv. Catarrhini not flat-nosed

1. Cercopithecoidae (Old World Monkeys)a. Cercopithecidae live in large groups

i. Cercopithicinae grass-adapted,

baboons (savannas), mandrils(forest), cercopithecines (arboreal),found primarily in Africa, except formacaques

ii. Colobinae primarily in Asia, exceptfor colobus, folivorous

vi. Hoinoidea1. Hylobatidae (Lesser Apes) gibbons and

siamangs, no prehensile tails, hooked handswithout prominent thumbs, move extremelyquickly, frugivorous, walk bipedally arboreally

and terrestrially2. Pongidae only in Southeast Asia

a. Ponginae (orangutan) - arborealb. Homininae birth interval due to long

period of gestation and care, no tailsi. Gorilla largest living primate,

adapted for upright posture, butcenter of gravity is so high that theyknuckle walk on the ground,leather-like pads on hands

ii. Pan (chimpanzees and bonobos)

structured like gorillas, but smalleriii. Homo

2) What is a Primate?a. Other orders within Mammalia have developed special

adaptations as they moved away from their primitivemammalian ancestor

b. Morphologyi. Pentadactyly five independently mobile fingers and

toesii. Flattened nails and sensitive pads on hands and feetiii. Retained generalized primitive mammalian bone

structure (collarbone, radius and ulna)iv. Retained generalized dental structure (4 types), may

have lost canines or molars depending on their diets1. Incisors have uses in biting into fruits2. Canines are used for ripping and cutting into

fruits and meats, showing in display3. Premolars rip/cut and chew, may shift towards

one or the other depending on diet


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4. Primitive mammals have tritubercular molarswith three cusps, in most primates, aquadritubercular system dominates, apes andhumans exhibit a Y5 pattern (more complextooth, more plant material)

5. Primitive mammals will have a 3:1:4:3 dentalstructure with a total of 44 teeth, many NewWorld Monkeys have 2:1:3:3 (36) pattern, OldWorld Monkeys, Apes, and humans have 2:1:2:3(32), some lemurs have variations on thesepatterns

a. Indri lemur has 2:1:2:3 on top and 2:0:2:3on bottom, Aye-Aye has 1:0:1:3 on topand 1:0:0:3 on bottom for gnawing andchewing

v. Visual powers elaborated (better than many other

mammals)1. Frontation movement of the eyes to the front

of the face, rather than sideways2. Convergence moving towards each other,

enables over-lapping vision, towardsstereoscopic vision

3. Hemi-decussation rather than each eye goingto the opposite side of the brain, the left side ofboth eyes goes to the right side of the brain andthe right side of both eyes goes to the left sideof the brain

vi. Reduction of smell1. Not necessarily the case for all primates, lemurs

combine olfactory and visual displays, as havemany other prosimians in New and Old Worldmonkeys, the increase in eye size has led to areduction of the olfactory system (cattirhine)

vii. Progressive development of the brain1. Relative to body size, primates have some of

the largest brains, though not the largestviii. Infant dependency last for longer

1. Long period over which an infant develops into

adult, during which it stays closely tied to itsparent(s)

ix. Trend towards sociality1. Nearly all diurnal, and some nocturnal species

are very social animalsx. R.D. Martin said that all of these traits are descriptive

of primates, but not necessarily unique to them (mayapply to other mammals)


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c. Unique features of Primatesi. Arboreal inhabitants of tropical and sub-tropical

forestsii. Extremities are adapted for prehension and arboreal

support

1. Grasping, nails and tactile pads with enhancedsensitivityiii. Hind-limb domination push off with their hind-limbs

rather than pulling with their fore-limbs, lateral footfallpattern (monkey gait, left foot to right hand, right footto left hand, diagonal sequence)

iv. Tarsi-fulcrumation elongated heel bone allows forprimates to leap, different balance

v. Large eyes in relation to skull size, post-orbital bar(eyeball completely enclosed by bone), frontation andconvergence leading to overlapping vision

vi. Petrosal bulla the bulla is the bone that covers innerear, only in primates (and plesiadopoids) use thepetrosal as this bone

vii. Specialized sulcal pattern (troughs in the grey mattersof the brain)

viii. Long gestation period (slow fetal and pre-natalgrowth), late maturity, and long life-span relative tomothers body size

ix. Small litters of precocial (not able to liveindependently of parents) infants

x. Dentition maximum of two incisors, molars and pre-

molars are relatively unspecialized, cusps on molars,lower molars have a grinding basin (talonid)

xi. Gregarious and social3) Evolution of Primates

a. Reptiles (300 MYA) Mammals (200 MYA) Pre-Archontan(insectivorous, tree shrew like) Mammals (120 MYA) Archonta (Plesiadaformes) (60-65 MYA) Euprimates (35-60MYA)

b. Archonta contains the orders Dermatptera (flying lemurs),Chrioptera (bats), Scandentia (tree shrews), plesiadaformes,euprimates

c. What major adaptive shift led to this set of adaptations?Why did primates of modern aspect evolve?

d. Currently 4 theories concerning primate originsi. Classic Arboreal Theory (Grafton Elliot Smith, Wood

Jones, W.E. Le Gros Clark)1. Shift from ground insectivore to trees became a

successful lineage by depending more on visionand touch rather than smell


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2. Led to hand-eye coordination, larger brains3. To acquire an arboreal way of life demands

prehensile functions of the limbs, a high degreeof visual acuity, and the accurate control andcoordination of muscular activity by a well-

developed brainii. Plesiadapoids were the first primates (Fred Szalay)1. Marker traits petrosal auditory bulla2. Features of the molar teeth, moved into trees

and began eating fruits3. Features of the ankles and wrists4. Not like primates claws and nails, long snout,

laterally facing eyes, basically insectivoreadaptations

iii. Visually-oriented predators (Matt Cartmill)1. Plesiadapoids are not primates, many did not

have primate-like dentition, features ofankles/wrists disputed, some dont havepetrosal bulla, some evolve to flying lemurs orother mammals

2. Problem of monophyly plesiadapoids evolvedinto a number of different modern mammals,have to make a taxonomic shift

3. The last common ancestor of all members of ataxon must also be member of that taxon

4. If exclusively arboreal mammals exist and aresuccessful without primate adaptations,

something is wrong with the arboreal theory ofprimate evolution

5. Of 13 orders of terrestrial mammals, 9 havearboreal forms, may of which do not haveprimate adaptations

a. Squirrels are not at a disadvantagedespite lack of primate adaptations, retainprimitive mammalian bone structure,clearly another way to exploit arborealhabitat

6. Comparative method

a. Claws highway branches (larger thantheir body size), take food to largehorizontal branches, often go to ground toretrieve food, descend face down

b. Fingers branches smaller than body size,use small terminal branches to feed

7. Primates are adapted to use terminal branchesof dense bush layer of the forest


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8. What is the adaptive significant of orbitalconvergence, frontation, and stereoscopy?

a. If aiming towards agility in trees, wouldexpect closely related animals to havegreater convergence in tree forms, faster,

more acrobatic forms would have moreconvergenceb. Neither prediction held true: in

marsupials, squirrels, tree shrews, andcarnivores, no greater convergence inarboreal forms, slowest primates have thegreatest convergence

c. Like cats and owls, earliest primates werevisually-orientated predators of the smallbranch milieu of the bushes and trees,moved into a new niche

9. Problems with the theorya. Only a very few of the 100 prosimians eat

over 50% insects, most are omnivorousb. Omnivory is the primitive condition of

primates morphologically (dentition andgut tract)

c. Most convergent eyes found in slowlorises (90% of diet is fruit and gums, ofthe insects they do eat, they are slow-moving, smelly, and conspicuous)

d. Hearing is the main sense used by other

fast moving nocturnal primates andinsects mostly ambushed on the ground

e. Cats use hearing mainly and eye anatomyis only superficially similar to that ofprimates

f. Many strictly plant-eating arborealmammals have convergent eyes(primates, sloths, koalas, phalangeridmarsupials) and many predatory birds

g. The animals with the visual system mostsimilar to that of primates are

megachiroptera (fruit bats)iv. Angiosperm coevolution (Robert Sussman)

1. What was happening on earth 60-120 MYA,when the earliest primates were evolving?

2. What adaptive niche were the earliest primatesexploiting?

3. Frugivorous birds, bats, and primates areimportant because the pollinate flowers and,


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more importantly, disperse fruits4. Birds were few and insignificant 65 MYA, some

very primitive mammals, reptiles dominatedlandscape and most niches, most trees weregymnosperms, angiosperms prominent in edge

regions, important after disturbance5. Dinosaurs kept angiosperms in check, despitevery rapid reproduction, never reaches treeheight, maintained for millions of years

6. With extinction of dinosaurs came fall ofgymnosperms, either killed by the same thing orangiosperms were no longer kept in check

a. Allowed more dense growth ofangiosperms, more shade toleranceseeds, larger seeds stored moreresources, allowed for taller growth,

slower reproductive turnoveri. Movement from r-selection to k-

selection, fewer large seeds, ratherthan many small

b. Rapid evolution of these new angiospermsduring this Paleocene period

7. Mammals and birds no longer have to competewith the dinosaurs, and plenty of niches areopen with emergence of these largeangiosperms

a. Mammals could go after the large seeds,

so plants develop nutritious covers for theseeds, animal takes seed and depositsaway from mother tree

b. Mammals can move into the trees to takeon an arboreal lifestyle, pre-cursors ofprimates

c. Radiation of tropical rainforest emergestoward the end of the Paleocene

i. Plesiadapoids are a good exampleof movement of mammals movinginto these arboreal niches, one of

these probably evolved into modernprimates

ii. Begin as insectivores, but frugivoresemerge within the radiation, someare completely folivorous

8. The Eocene is the period during which thisadaptive radiation come to fruition, now largeplants with large seeds dominate the landscape,


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modern taxa are present in modern rainforests,modern families and genera of angiosperms arepresent

a. Major avian radiation to fill nichesprovided by large fruits

b. Major mammalian (rodents, rabbits, andhoofed animals) radiation, bats and bat-adapted fruit

c. First euprimates develop during earlyEocene

d. Animals are better able to exploit theterminal branches of these angiosperms(gums, fruits, leaves, insects that eatthese things)

e. Primates, with their grasping appendages,can exploit this new niche very effectively

f. Frontation and Convergence develop in anumber of mammal groups, some ofwhich feed solely on foliage, evolve tosee through clutter in the vegetation

i. 2 forward facing eyes can see 2 to 8times further in a highly clutteredenvironment than one lone eye

ii. Strong correlation betweenleafiness and convergence relativeto body mass

g. Most likely hypothesis based on the time

frame in which grasping limbs, primatedentition, and orbital convergenceevolved

v. Cartmill: If the first euprimates had grasping feet andblunt teeth adapted for eating fruit, but retained smalldivergent orbits, the terminal branch feedinghypothesis would be supported, thus disproving hisown theory

1. Carpolestes simpsonii (plesiadapoid) fossildiscovered basically has primate grasping hindfoot, spent little time on large diameter

supports, occupied small branch niche, low-crowned molar teeth, primarily fruit eaters, alsoexhibits small divergent orbits

vi. The question remains where we should make thecutoff for primates in the taxonomy, is Carpolestes thecommon ancestor for more than just the primatephylogeny

e. Several of the previously recognized unique


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characteristics of living primates were acquiredincrementally during the course of primate-ancestorevolution

f. Consistent with the idea that primates acquired their suiteof diagnostic features through diffuse coevolution with

angiosperms during the Paleocene-Eocene transitionLorisiformes1) Taxonomy has been the one consistently inconsistent aspect of

primatology, many more species of lorisiformes are nowrecognized than decades ago, in nocturnal primates, similarlooking animals turned out to be different species, matingvocalizations are now the most accurate way to distinguish

a. Now, for conservation purposes, new species are beingmade out of small populations discovered in new systems ormembers of a single population that appear slightly different

2) Using primarily Charles-Dominques study of these five species in

Gabona. Determines the type of habitat each species used

i. Discontinuous study 836 first sightings (42 monthsover 8 years), notes the height in the forest,orientation of the branches they used, the diameter ofthese branches, and nature of the support

b. Determines the dieti. Shot animals outside of his study site (201 specimen

of all different species, sizes, times of year, and timesof day), divided into animal, fruit or gum

3) Galaginae (fast-moving African galagos)

a. Synterritoriality found in some galagos, lemurs, and tarsiers,one male and one female home ranges overlap(corresponding home ranges), may have multiple femalessharing one home range, do not move around together atnight, may sleep together in the same nest

b. Galagoides demidovii (Demidoffs Dwarf) 60 gramsi. Canopy dwellers, most of the time from 10-20 meters

in primary forest, 64% were less than 1 cm, most ofthe rest of the time on branches less than 5 cm, 22%on horizontal, 30% on oblique, and only 48% onvertical branches (or so Charles-Dominque thought,

he was actually studying primarily thomasi)ii. 70% of the diet was animal, 19% was fruit, and 10%

was gum (insectivore)iii. Galagoides thomasi 60 grams

1. They were found in edge forest, from 0-10meters in secondary forest

c. Sciurochieirus gabonensis (Gabon squirrel) 260 gramsi. Spent most of the time in the understory, 0-2 meters


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in primary forest, 60% of the time on small branches(under 5 cm), 6% on horizontal, 13% on oblique, andonly 81% on vertical branches, specialized for thevertical branches

ii. 25% of the diet was animal, 73% was fruit, and 5%

was gum (frugivore), mostly fallen to the ground,already ripe, not being fed upon by other pottoiii. Most generalized form of sociality in nocturnal

prosimians, females have fairly small home ranges,that overlap quite a bit, and multiple females willshare home range and avoid females form other homeranges, will form nesting groups within (1 to 5individuals)

iv. Males have fairly large home ranges (30 hectares vs.10 in females, overlap more than one female group,males avoid one another, do not form nesting groups,

will mate with females in their home range, if twomales overlap with a female home range, females willpotentially mate with both males

v. Smaller males are forced to the periphery or mayhave very irregular ranges

vi. Reproductive harems develop whereby one maletends to mate with more than one female, interactthroughout the year

vii. Evolution towards one-male group in harshenvironments because population relies on females,one male can mate with many females

viii. Males are territorial, females are less territorial,though do try to avoid each other

ix. Female offspring stays with mother long afterweaning, leads to matriarchal groups, though malesare forced out after puberty, young are left in nests bymothers

1. Some species have more tolerance for males,may have home ranges within the ranges ofother males

x. Urine markings for social, territorial purposes, Charles-Dominque found that females move throughout the

whole range, spent more time urine marking aroundnests and 3.7 times per hour in overlap zones (withother females), communicated where they were sothey could avoid each other, male can also tell matingcondition (estrous) by marking in overlap zonebetween male and female

xi. Two types of calls: alarm is never answered so thatthey can remain hidden, croaking call is always


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answered for communication purposes, attracts malesand tells females to stay away (8 times more likely inoverlap zones)

d. Euoticus elegantulus (Southern needle-clawed) 300 gramsi. Found from the ground all the way up to 50 meters,

moves primarily vertically, use nails as a secondaryadaptation to claws to move along highway branches,22% on horizontal, 51% on oblique, and only 27% onvertical branches, specialized claws and dentitionallows them to fit into a unique niche between the twoother species

ii. 21% of the diet was animal, 10% was fruit, and 75%was gum

iii. 78% of insect diet are beetles and moths (fast movinginsects)

iv. Lives in the canopy with potto, both eat gums, during

dry season, potto eats only fruits and insects whileelegantulus focuses on gums, uses canine-like incisorsto get to it

e. Protection against predation - very fast moving, can usuallyoutrun or outmaneuver predators, warning calls, mobbingbehavior

4) Perodicticinae (African slow lorises)a. Perodicticus potto (Western potto) 1100 grams

i. Remains in one place without moving when faced witha predator, faces the predator, adaptations to handsand feet (maximizes blood flow) that allow it to stick

to the branch for a long time, spines on its neck thatallow it to bend its head forward, revealing only thesespines, butts the predator, when faced with a snake,will drop to the bottom of the branch and falls to theground, then moves away relatively quickly once onthe forest floor (7 out of 10 times), difficult to findthem afterwards

1. Researchers have never found a potto in apredators stomach contents

ii. Canopy dweller, 10-30 meters in the primary forest, inthe secondary forest it was 10-15 meters up,

locomotion was climbing rather than jumping,branches went from 1-30 cm in diameter, found 39%on horizontal, 35% on oblique, and only 26% onvertical branches

iii. 10% of the diet was animal, 65% was fruit, and 21%was gum

1. Actually consumed approximately the sameamount of insect mass as Archtocebus, both


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were going after the same thing, but becausepotto was much larger, had to supplementinsect with fruit

2. Eats primarily ants (formic acid), centipedes(iodine), and crickets, all toxic, adaptations to

detoxify3. Tested whether these species prefer toxicinsects or just eat them because they areavailable, actually prefer moths without theirwings, but cannot catch them

iv. Females do not form nesting groups because they donot go back to nests (slow moving), young are carriedon fur, baby parking when they feed, female rangesare relatively small and do overlap while males havelarger home ranges that overlap multiple femaleranges

v. Female offspring , as well as males, develop their ownhome ranges after weaning, no matriarchies

vi. Depend more on scent marking rather than callsbecause they do not want to attract attention ofpredators

b. Arctocebus calabarensis (Calabar angwantibo) 200 gramsi. Different set of smaller predators, rather than facing

the predator, will move into dense vegetation and willface away, tail almost acts as a target, will bite thenose of the predator, when it is shaken off, it will letgo of its grip and fall to the ground

ii. Stayed in the undergrowth, primarily between 0-5meters, may move upward if disturbed, spent time inbushes and on lianas between bushes, 40% of theirsupports were less than 1 cm, 52% were 1-10 cm,found 20% on horizontal, 30% on oblique, and 50% ofthe time on vertical supports

iii. 85% of the diet was animal, 14% was fruit, and 0%was gum (insectivore)

iv. 70% of their insects are caterpillars, most of which arealso toxic, large quantity available because otheranimals do not predate upon them often, slow-

moving, smelly or visiblec. Protection against predation - have developed specialized

anti-predation techniques, very cryptic, slow-moving and trynot to disturb vegetation

5) Lorisinae (Asian slow lorises)a. Protection against predation - smell bad, glands secrete

toxins, can kill a human fairly easily, will lick babies to coverthem with these toxins


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The Adaptive Array of the Lemurs of Madagascar1) About 500 miles long and 250 miles wide, third largest island in

the world, has almost all of the same ecosystems as can be foundon mainland Africa

a. The central plateau is high and wet, where most of thepeople live, deforested a great deal of the land area thoughwas probably densely forested before humans settled

b. Eastern portion has mountains and rainforest areasc. The north has deciduous forest, gets drier along the western

coast until desert in the southern portiond. Major groups are divided into east (adapted to rainforest)

and north and west (adapted to drier deciduous forest),another split is between nocturnal and diurnal(approximately 50% each)

i. Most of the new species being discovered are in the

east where one would expect higher diversity, veryfew species are found in both habitat types

ii. Most Lemuridae are diurnal, a few are cathemeral(active during the day and night), none are completelynocturnal, Lepilemuridae are all nocturnal, Indriidaeare primarily diurnal

iii. At least 16 species of lemur have gone extinct withinthe past 2000 years (since humans came to theisland), all of which were larger than our modernspecies, all filled different niches

e. Southwestern and Western Forests

i. 3 diurnal species (only 2 as you move further south)and 5 nocturnal species

f. Northwestern Forestsi. 5 diurnal species, though Lemur catta has fallen out,

replaced by arboreal species, 6 nocturnal speciesg. Eastern Forests

i. 7 diurnal species (more arboreal and bamboo-eatingspecies), 6 nocturnal species (different from thosefound in NW Forests)

ii. Diversified the lemurs (belong to more families)h. Western Lemurs from October to January, have many fruits

and flowers, between May and September, conditionsbecome much harsher as fruits and flowers disappear duringthe dry season

i. Lemur catta (Diurnal) Ring-tailed Lemur1. Only living lemur that spends the majority of its

time on the ground (33%), and varying amountsof time in all other stratum, with the exceptionof the emergent layer, feeds mostly on the


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ground and below the canopy, travels primarilyon the ground

2. Mainly frugivorous, continues eating fruits andherbs off the ground during the dry season, butwill eat a slightly generalized diet of leaves

ii. Eulemur fulvus rufus (Diurnal) Brown Lemur1. Almost exactly the same as ring-tailed lemur,very subtle and specific differences, spend mosttime in the canopy stratum of the forest (71%),most of the feeding time is in the region as well,travel through the canopy

2. Specialized folivore, feeds a great deal on a fewspecies (11), 3 species make up 80%, hasadapted to the toxins of these plants, prefersfruits during the wet season, but will eat leavesduring dry season

iii. Propithecus verreauxi (Diurnal)1. Much larger, about the size of a gibbon rather

than a cat, spend most of their time on thevertical trunks beneath the canopy, and sometime in the canopy and the emergents where itdoes most of its feeding, travel beneath thecanopy, but off the ground

2. Generalized folivore, lots of different species ofplants (85), limit the amount of any one toxin,24 species make up 80% of their diet

iv. Cheiriogaleus medius (Nocturnal) Fat-tailed Dwarf

Lemur1. Unlike any other primate, actually hibernates

during the dry season when fruits and flowersdisappear, stay in hollows in tree trunks,emerges in November, quite active during therainy season, opportunistic frugivore, increaseamount of food with some insects, prior tohibernation, will accumulate fats from fruits intheir tails, may gain up to 50% of their bodyweight in tail

2. Scurry like mice, not particularly agile, fat tail is

not conducive to very acrobatic locomotion,come to the ground for insects, but focusprimarily on fruits

v. Microcebus murinus (Nocturnal) Mouse Lemur1. Go into torpor (state of partial hibernation),

females are less active, come out of torpor lessoften than males, people believed thepopulations were strongly weighted towards


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males, actually just during the dry season, stayin hollows for a number of consecutive days

2. Live mainly in the canopy and eat primarilyfruits and insects (approximately 50% of diet ismistletoe-like fruit)

vi. Microcebus (Mirza) coquereli (Nocturnal)1. Lives like Mouse lemur in dense foliage ofcanopy, eats insects and fruits, during the dryseason, focuses on a specific insect, eating itssecretion rather than the insect itself, highcarbohydrate, so can make it through dryseason without fruit

2. All three species eat the same things during thewet season when resources are abundant, allhave very special adaptations to get themthrough the dry season

vii. Phaner furcifer (Nocturnal)1. Active throughout the year, specialized to focus

on gums throughout the year, especially duringthe dry season, moves through the canopy bothvertically and horizontally, will eat fruits andfloral nectar during the wet season

2. Adaptations for eating gums: has claws(secondarily adapted from nails), procumbentincisors for gnawing into bark, long, pointedtongue for reaching gums

viii. Lepilemur mustelinus (Nocturnal)

1. Specialized folivore, can eat mature leaves(91% of diet), which many primates havetrouble digesting, large caecum and wide colonadapted for eating leaves, shearing crests onmolars adapted for grinding leaves, can detoxifycertain toxins, so can eat as many as 24species, or as few as 2

i. Northern Lemursi. Eulemur fulvus fulvus brown lemur

1. Different from the E. f. rufus found in the west2. With E. mongoz: niches overlap heavily during

wet season, during resource-poor season, fulvusremains pretty much the same, but mongozbecomes nocturnal, will eat primarily flowersand nectaries (81% of diet), some fruits, andvery few leaves

3. With E. macaco: nobody has done a good studyon their interactions, assume they divide up thelandscape


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4. With E. coronatus: found primarily in the understory while the brown lemur is found primarily inthe middle story, this means they are usingdifferent trees, 18% of crowned lemur diet isshared with brown lemur, about 75% is different

(similar species, but different parts of the treesdue to their choice in strata)ii. Eulemur mongoz, Eulemur macaco, Eulemur

coronatus1. Ecological equivalents with one another,

replaced as you move north, ranges do notoverlap, though all overlap with E. fulvus

iii. Propithecus spp.1. A number of different species are ecological

equivalents, all fill the same niches, so willnever be found in the same area, changes as

you move around the islandiv. Hapalemur griseusv. Avahi langier (Nocturnal folivore)vi. Lepilemur mustelinus (Nocturnal folivore)vii. All other nocturnal species also present

j. Eastern Lemursi. Eulemur fulvus rufous (Frugivore)

1. With E. rubriventer: only 1 species in their top 5most commonly eaten plant species overlapsbetween the two, different species, but similarparts, though E. rubriventer eats more fruits and

less leaves than E. fulvus, not as well adapted totoxic parts of the plant

2. With V. variegata: most of their time is spent uphigher in the forest (15-25 meters) while E.fulvus tends to be lower, V. variegata is aspecialized frugivore in these taller trees

ii. Eulemur rubriventer (Frugivore)1. Live in pair bonded groups rather than large

social collectionsiii. Varecia variegata (Frugivore)iv. Propithecus diadema (Folivore)

1. Multi-female groups2. With I. indri: eat similar things, but at different

rates, Indri is much more specialized towardsleaves, while P. diadema eats almost as muchfruit (actually seeds within) as leaves

v. Indri indri (Folivore)1. Family groups (mother, father, and offspring),

probably related to resource distribution


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vi. Hapalemur grieus (Bamboo and Grass Eaters)1. Most generalized, smaller, different types of

grasses and bamboo, sometimes fruits as well,detoxifies bamboo

vii. Hapalemur aureus (Bamboo and Grass Eaters)

1. Very localized, slightly more generalized than H.simus, fairly small, detoxifies bambooviii. Hapelemur simus (Bamboo and Grass Eaters)

1. Highly specialized for one type of bamboo,bigger, all three detoxify bamboo differently

k. Lemur Conservationi. 85% correlation between human population density

increase and deforestation of forested regionsii. After economic surge that brought people into the city

in the 1970s, people began returning to rural areasand deforesting

1. Cutting forests for corn plantations, firewood,and slash and burn agriculture

Quantitative Study of Primates1) A study was performed in which a Brown Lemur (Eulemur fulvus

fulvus) was released in an area where Ring-tailed Lemurs (Lemurcatta) were found, but where Brown Lemurs were not normallyfound, the Brown actually adapted completely to the Ring-tailslifestyle

a. This was presumed to mean that the two species wouldcompete directly with one another

b. Hypothesis was that the habitat and diet was actually

divided between the two species when they were foundtogether

i. Found three different types of forests (catta alone,fulvus alone, both together) to determine behavioraldifferences

2) Needed to collect quantitative dataa. Scan-Sampling Method every five minutes, determine the

number of individuals (single or pair) participating in eachtype of task (feeding, resting, grooming, individual moving,group travelling, other), also noted which level of the foreststrata they were performing these tasks, ad-lib notes as well

for other, may take note of plant species they are eatingb. Ring-tailed Lemur are found throughout the south of the

island, Brown Lemur are found everywhere else (wetterforests), despite differences in coat color, actually verysimilar, both species ranges are sympatric with Propithecusverreauxi

i. In most cases, when there is an edge habitat, it ismore diverse than the main forest and nearby


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savannah or grasslandii. Ring-tails tend to be found in edge forest and brush as

well as gallery forest, while Browns were found in onlygallery

iii. Structure of forest at three different sites was similar,

though the species differedc. Utilization of Forest Stratai. Regardless of Activity

1. Brown Lemur spent the great majority of theirtime in levels 3, 4, and 5 (essentially remains inthe canopy), Ring-tail spend a lot of time on thegroup and significant time in 3 and 4 (movevertically a great deal), unlike Brown lemur, theRing-tail actually spent 60% of their time at theedge or in the brush areas

2. Apparently activity did not change when the two

species were together or separate3. Unlike the Brown Lemur, and all other lemurs,

heel of the Ring-tail is not covered in hair, morelike monkeys an apes, different means oflocomotion due to movement on ground ratherthan in trees

a. Amount of rotation at joints in Brownlemur is much more like arborealprimates, while Ring-tails were more liketerrestrial primates (more stability),densities differ this way

d. Utilization of Horizontal Spacei. Ring-tails covered a large portion of the forest, in and

out, one group of 19 animals covered about 20 squarehectares, 9 groups of 5-7 Brown Lemurs utilized thesame 20 hectare space, remained in small homeranges of 1-1.5 hectares

ii. Ring-tails would move approximately 1000 meters in asingle day, cover their entire range every 7-10 days,covering a number of different habitat types in asingle day

iii. Brown Lemurs moved about 250 meters within much

smaller day range, but tended to move around almosttheir entire range in a single day

e. Dieti. Ring-tails ate a much larger variety (24 species) of

plants, very similar between sites, only about 25% oftheir diet is Tamarindus indica no matter what theseason, even during the dry season, a significantportion of the diet came from fruits and herbs (leaves


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make up 43% and 24% of dry and wet season diet,respectively)

1. Adjust their home range to find what trees wereflowering at any given point during the year,flock to that for an number of days (frugivore)

2. Due to their exploitation of the ground andability to move over large areasii. Brown Lemurs ate a small variety (8 species),

Tamarindus indica could make up nearly 80% of thediet during the dry season (eating primarily leaves),though only about 50% in the wet season (eatingmuch more fruits and flowers)

1. What they ate really depended on their homerange, some group could get fruit while othershad no flowering trees in their home range(folivore)

f. Activity Budgetsi. Ring tails would eat a bit in the morning, but primarily

rest, feed throughout most of the day, rest for a shortperiod during the hottest time of the day, continueeating into the afternoon, rest towards the night

ii. Brown Lemur would eat primarily in the morning andafternoon (sometimes going into the night), rest forthe majority of the middle of the day

g. Group size and compositioni. Both species live in multi-male multi-female groups

(3.4 male 4.3 female in Brown Lemur, 6 male 6.3

female in Ring-tailed Lemur), also have some juveniles(1.2 in fulvus, 3 in catta) and infants (1 and 3,respectively)

ii. Ring-tailed lemurs tend to have larger groups (10-30members) with a distinct hierarchy with sub-groups,central males in center with females, sub-adult malesare peripheral, females also have hierarchy based onmatrilines (alpha female family is dominant to betafemale)

iii. Brown lemurs tend to have smaller groups (4-17members) in an egalitarian manner with no real

hierarchyh. Summary

i. Social structure and behavior are directly related totheir differential use of time, food, and space

ii. Behave the same whether they are alone or together,no character displacement, behavior based on longevolutionary history utilizing different niches (Brownadapted to wet forests while ring-tails are adapted to


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drier deciduous forests where resources are moreuneven)

iii. Parallels between behavior and ecology in thesespecies and similarly-adapted monkeys in Africa(higher density of folivores, smaller home ranges in

arboreal)iv. Can relate morpho-physiology, social behavior andstructure to ecological differences

Groups and Social Structure1) Groups are a number of individuals of the same species who

interact socially more frequently among themselves than otherconspecifics, and these group members exhibit different behaviorto conspecifics not in their group, and occupy the same homerange, groups also tend to be fairly stable

2) Social Structure is divided into group structure and populationsstructure

a. Group structure is the size and composition of the groupb. Population Structure is the distribution of groups within the

population3) Social Organization is the pattern of interactions between

individuals both within and between groups4) Home Range is the area over which group members travel in

pursuit of their everyday tasks over their lifetimea. Core Area is the portion of the home range used with

greater regularity than other areas (may define as 50% or95%), tend to be most resource-rich

5) Day Range is where the group travels in any given day

6) Territoriality is the behavioral mechanisms that control spacebetween two animals such as ritualized behavioral displays, mustalso have very little overlap between groups to be consideredterritorial

7) Types of Group Structures we find in primatesa. Solitary but Social sleep together, but do not move

together, orangutans and most nocturnal prosimiansb. Multi-male/Multi-female group more than one male and

more than one female, found mostly in diurnal lemurs, manyNew World Monkeys, most terrestrial African Monkeys, somecolobines, and gorillas

c. One-male/Multi-female group harem with one male andmany females which whom he may mate, Old WorldMonkeys

d. Fission-Fusion number of animals interact in a community,but come together and move apart from time to time

i. (New World) Spider-monkeys different individuals ondifferent days, but always the same animals in thelong term


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ii. Chimpanzees live in large groupsiii. Baboons not the individuals that come together and

break up, but subgroups (Gelata baboons have one-male reproductive groups, Hamadryas have one-malegroups together in bands and even larger troops)

e. Pair-bonding Groups male and female with their offspring,found in Indri, rubriventer spp., colocebus, and gibbons,tend to be territorial

f. Polyandrous groups one reproducing female with morethan one male in the group, may also have non-reproductivefemales, found only in callitrichids

Primate Ecology Part I

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