Introduction to Archaeology and Palaeoanthropology:

 

Humanity's Journeys

 

Dr. Kathryn Denning

 

Anth 2140, Sept 2005 - Apr 2006

 

   (Young Chimpanzee)

 

1 Nov 2005... Welcome!

 

 

Plan for the day

 

1   Course business/ announcements...

2   Continuing... our primate relatives - biology and behaviour - and early hominids

 

 

Schedule

For today/tomorrow, KIT: Macroevolution and the Early Primates, Something New and Different, and Cat in the Human Cradle. FAGAN Ch 8 Human origins.

Tomorrow in tutorial: Video: The Story of Lucy  (about palaeoanthropology and Australopithecus afarensis)

Slowing down a bit: See revised reading schedule. Basically, next week is catch up / review and then we'll resume.  i.e. the schedule has been delayed one week.

So for next week: REVIEW in lecture. CATCH UP on your readings.

Quiz 2 will be held in tutorial on Weds Nov 9:  Review guidelines will be posted here shortly.

 

 

 

From class last week

 

 

Primate Learning and Behavior

Have a greater dependence on flexible, learned behavior.

Tend to live in social groups.

Males are permanent members of many primate social groups, a situation unusual among mammals.

Arboreal Hypothesis

Arboreal (tree) living was the most important factor in the evolution of primates.

Prehensile hand is adapted to climbing in the trees.

A variety of foods led to the omnivorous diet and generalized dentition.

Visual Predation Hypothesis

Primates may have first adapted to shrubby forest undergrowth and the lowest tiers of the forest canopy.

Forward facing eyes enabled primates to judge distance when grabbing for insects.

Flowering plants may have influenced primate evolution.

Primate Habitats

Most live in tropical or semitropical areas of the new and old worlds.

Most are arboreal, living in forest or woodland habitats.

No nonhuman primate is adapted to a fully terrestrial environment; all spend some time in the trees.

Primate Diet and Teeth

Generally omnivorous, reflected in their generalized dentition.

Most eat a combination of fruits, leaves, and insects.

Some primates kill and eat small mammals.

Some primates are dietary specialists for leaves.

Most have four types of teeth: incisors, canines, premolars and molars.

 

Primate Locomotion

Most primates are quadrupedal, using all four limbs in their locomotion.

Arm swinging is found among the apes.

Siamangs of southeast Asia use this exclusively.

Monkeys that use a combination of leaping and arm swinging are termed semibrachiators.

Prehensile tails, found only among the new world monkeys, are used as an aid to locomotion.

 

Below: 4 main locomotor patterns, although n.b. primates are flexible and able to move in more than one way (unlike some animals, e.g. dogs, horses are more restricted in their locomotion)

Skeletons are from:

*Terrestrial quadruped (savanna baboon)             

*Arboreal (bearded saki) New World - prehensile tail

*Vertical clinger/leaper (indri)

*Brachiator (gibbon)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

More detail on the locomotor pattern and its connection to habitat and behaviour: 

 

Terrestrial quadrupeds

Front and hind limbs almost even length (forelimbs 90% of hind limb length), fast runners. Food/environment: tend to live in savanna or open areas, sit on the ground to eat seeds etc.  Often tend to sleep in trees or on cliffs to avoid predators. Usually live in large groups. Tail not prehensile.

 

 

 

 

 

 

 

Savanna baboon

Papio cynocephalus

 

 

Arboreal - tend to walk on top of branches more than swinging below them (think squirrels). Forelimbs 70-80% length of hind limbs. (Need more power in the back for jumping than in the front.) If in the New World, often have prehensile tails. In the Old World, often have long tails which are used for counterbalancing, but are not prehensile. Hands and feet are good for grasping.

 

 

 

 

 

 

 

 

 

White-nosed Bearded Saki (Chiroptes albinasus)

 

Prehensile Tail: interestingly, also seen in other orders of arboreal animals, like lizards, porcupines, opossums...

Spider monkey, right -->

 

 

 

 

 

 

 

http://primates.com/monkeys/spidermonkey.html

 

 

 

 

 

 

 

Vertical clingers/leapers

Most often seen in prosimians (lemurs, tarsiers) - clinging to tree trunks. Hands very good for grasping.  Live in forest: some  eat bugs, tree sap, invertebrates, while others species eat leaves, fruit etc. Tend to live in small colonies, pairs, or to be mostly solitary.

 

 

INDRI  (Indri indri)

 

 

 

 

Tarsier: another vertical clinger/leaper. Note pads on hands and huge (immobile!) eyes.

http://primates.com/philippine-tarsier.html  (n.b. not actually smallest 'monkey' ... that's the pygmy marmoset, over in the New World)

 

 

Brachiators/ arm swingers: apes, including lesser apes (gibbons and siamangs), great apes (chimps, bonobos, gorillas, orangs). Generally longer arms than legs. Can support entire body hanging from one arm.  Live in forest: tend to hang from branches and eat fruit.

Gibbons: live in pairs or very small family groups. 

(Humans too... our legs are long by comparison, but we still have the suspensory shoulder adaptation.)

 

Gibbon  (Hylobates sp)

 

 

 

 

 

 

 

 

 

 

 

 

 

N.b. other locomotor variants

Orangs - quadrumanous - i.e. feet and hands all have opposable thumbs! primarily arboreal, use feet just like hands, unbelievably flexible. Eat fruit, tend to live alone or in very small groups.

Gorillas and chimps - knuckle-walkers but also climb trees. Gorillas live in small extended family groups and primarily eat leaves/stems, chimps in somewhat larger groups and primarily eat fruit.

Bipedalism - mostly just us and our ancestors -- the point at which habitual bipedalism emerged is much-discussed -- but bipedalism does occur occasionally in many primates. e.g. the sifaka bounces along bipedally, injured chimps may walk bipedally, and occasionally a monkey will develop the habit too.

Sifaka travelling bipedally http://primates.com/lemurs/sifbab.html

 

Another e.g. Natasha the bipedal monkey (unusual): http://www.primates.com/monkeys/bipedal.html

 

 

 

Finetuned adaptations in primates: Example, Aye-aye finger

 

 

 

 

 

 

 

 

 

 

 

n.b. Extant primate skeletons and knowledge of primate behaviour helps us to understand the behaviour of fossil primates, including hominids. e.g. knees, feet, big toe, forearms, neck position, pelvis

 

Primate Behavior

 

Primates exist in a tremendous range of shapes and sizes, from the pygmy marmoset to the gorilla. They also have a host of different behaviour patterns:

-some live in large groups, others in small groups, pairs, or mostly alone

-eat anything from bugs to fruit to other animals

- in some species, males and females look the same, and in others they differ

- live anywhere from snow to tropics

 

e.g. Japanese Macaque

http://primates.com/snowmonkeys/snowmonkey.html

 

e.g. Pygmy Marmoset: http://www.rarespecies.org/pygmy2.htm

 

 

Pygmy Marmosets.

Note the twins -- normal for callitrichids (marmosets and tamarins)

--

cared for by both parents, father carries them

 

http://www.rarespecies.org/pygmy.htm

 

 

Photo gallery showing diversity of primates http://primates.com/

 

 

 

Communication

Raised body hair is an example of an autonomic response.

Vocalizations and branch shaking are examples of deliberate communication.

Reassurance is communicated through hugging or holding hands.

The fear grin, seen in all primates, indicates fear and submission.

Displays communicate emotional states.

 

Many primate expressions are familiar to us, but n.b. their function has shifted a bit in humans. e.g. the fear grin and our smile can be similar.

N.b. Staring is very bad behaviour among primates.

 

 

 

 

 

Aggression

Primates might defend a core area within their permanent home.

Jane Goodall witnessed unprovoked, brutal attacks of chimpanzees by other chimpanzees.... apparently territorial at least some of the time

Territoriality and acquisition of females are the motives suggested for chimpanzee male aggression.

 

Affiliative Behaviors

Reinforce bonds between individuals and enhance group stability:

Grooming reinforces social bonds.

Hugging, kissing and grooming are all forms used in reconciliation.

Relationships are crucial to nonhuman primates and the bonds between individuals can last a lifetime.

Altruism, behaviors that benefit another while posing risk to oneself, are common in primate species.

 

http://primates.com/orangutans/oran.html

 

 

Patterns of Reproduction

In most primate societies, sexual behavior is tied to the female’s reproductive cycle. Females are not always receptive -- and males are not always interested. Each female has a little flurry of mating activity for a while each cycle, apparently corresponding with ovulation. Many have visual cues, e.g. swelling or colouring of genitalia or even secondary tissue. http://www.sciencebuff.org/orangutan_estrus_cycle_details.php

Male and female Bonobos may mate even when the female is not in estrus, a behavior that is not typical of chimpanzees or other primates. (Also more same-sex activity in this species)

Non-human primates have a range of mating patterns, ranging from permanent pairs (gibbons and callitrichids) to `favourite` partners, to more widespread mating.

Permanent bonding is not common among nonhuman primates.... but it does exist. So do `consortships`.

 

Reproductive Strategies

Primates produce only a few young in whom they invest a tremendous amount of parental care. (k –selected rather than r-selected)

The young are very dependent upon their mothers and the group.

http://primates.com/orangutans/baby.htm

 

And young primates (like many young mammals) play a lot

http://primates.com/snowmonkeys/snowball.html

 

 

Mothers and Infants

http://www.hedweb.com/gorilfam.htm

 

The basic social unit among all primates is the female and her infants.

Monkeys raised without a mother were not able to form lasting affectional ties - Harlow.

The mother-infant relationship is often maintained throughout life.

The role of the male varies according to species: some (e.g. callitrichids) are very active parents, whereas others play no particular role.

Others in the social group may also engage in parenting behaviour, e.g. older siblings, other relatives.

 

Nonhuman Primate
Cultural Behavior

Cultural behavior is learned and passed from one generation to the next.

Chimpanzee culture includes tools such as termite fishing sticks and leaf sponges.

http://primates.com/chimps/chimpwat.htm

Chimpanzee tool use: http://news.nationalgeographic.com/news/2004/10/1006_041006_chimps.html

 

The Primate Continuum

Human brains are larger than primate brains, but the neurological processes are functionally the same.

Nonhuman primates think and have feelings. We may not understand them, but that does not disprove their presence.

An astonishing blindness: That humans are part of an evolutionary continuum is the basis for animal research, yet we cage nonhuman primates with little regard for their needs.

Captive primates should be maintained in social groups and have access to habitat enrichment programs.

 

 

photo by Tommy Hayne. Captive monkey in Vietnam, 1994

 

 

 

 

 

What can non-human primates tell us about human beings?

 

Notes from tutorial last week

 

Being careful about our inferences

"Back in the late 1920s, the anatomist Solly Zuckerman reported strong dominance hierarchies and high levels of 'aggression' and fighting among the large but confined hamadryas baboon colony at London Zoo, and developed an influential theory of social behavior based on these studies...Later researchers, observing baboon colonies in much larger enclosures or in the wild, failed to find similar levels of fighting. Instead, the groups seemed relatively peaceful and stable.

"It became obvious--and, with hindsight, it seems scarcely surprising--that the behavior of Zuckerman's baboon group had been dramatically modified by restricting the space within which its members had to coexist. The constraints of [the baboon group's space] had transformed the situation he wished to study and fundamentally misled him..."

(Rose, Steven; *Lifelines: Biology Beyond Determinism*; Oxford University Press, Oxford; 1998; pp. 28-29)

 

Why is this important?

Because of the conclusions about HUMANS that are drawn on the basis of primate studies.

This happens even at the highest levels of government. e.g. Francis Fukuyama, a political theorist who has been an advisor to the White House, uses chimpanzee behaviour to argue that aggressive, masculine-style politics are necessary on the international political scene.

http://www.foreignaffairs.org/19980901faessay1415/francis-fukuyama/women-and-the-evolution-of-world-politics.html

Whether you believe his conclusions or not, it is inappropriate to use non-human primate behaviour to justify or determine our own human choices. What if, instead of looking at specific episodes of violence among chimpanzees, he had focused upon peace-making behaviour among bonobos (who are more closely related to us anyway)? What would his conclusions have been then? Primate behaviour is extremely diverse -- so by choosing a different species, you can make any argument you like about human behaviour. It might be rhetorically effective, but that doesn't mean it's logical.

 (An answer to Fukuyama: http://www.foreignaffairs.org/19990101faresponse956/barbara-ehrenreich-katha-pollitt/fukuyama-s-follies-so-what-if-women-ruled-the-world.html )

 

 

Here's a nice article from primate researcher Frans DeWaal about our primate heritage: http://www.timesonline.co.uk/article/0,,2092-1848865,00.html

 

 

 

Like many higher-order vertebrates, primates have both innate and learned behaviour. Behavioural plasticity (capacity to change) is a key primate adaptation.

 

Theoretical systems for studying and explaining behaviour:

socioecology - examines relationships between components of the environment and behaviour (i.e. we would expect to see behaviours

sociobiology - looks at the relationship of natural selection and behaviour (i.e. we would expect to see behaviours that would maximize an individual`s success in spreading their genes and rearing their relatives to reproductive age)  - the case of infanticide among langurs

n.b. no one system can explain everything!

 

To understand behaviour in a species, including social structure, you need to understand:

* diet (including quantity, quality, caloric value of foods)

* spatial distribution of foods (lots everywhere, scattered, clumped...)

* distribution and reliability of water sources

* body size, basal metabolic rate (energy requirements)

* distribution and types of predators

* distribution of sleeping sites

* activity patterns - nocturnal, diurnal, crepuscular

* relationships with other (nonpredator) species, including primate and nonprimate

* impact of human activities (if primates are being observed, they are being impacted!)

 

Many variations are correlated to body size. E.g. male and female primates that live in pairs tend to be nearly the same size (gibbons), whereas in species that live in groups, there is more sexual dimorphism (gorillas, baboons)

 

Socioecology and Predation

Environmental factors influence on group size and structure.

Multimale and multifemale groups have an advantage when predation pressure is high.

Adult males may join forces to attack predators.

Savannah baboons have been known to kill domestic dogs and attack leopards and lions.

Solitary foraging may be due to diet and distribution of resources or predator avoidance.

 

Evolutionary Perspective

Natural selection acts on behavior just as it acts on physical characteristics.

Behavior is a phenotypic expression and genes code for specific behaviors.

Natural selection has a role in shaping primate behavior.

 

Criticism of the Evolutionary Perspective

Little data on:

The social behavior of large groups of animals.

Genetic relatedness through the male line.

Assigning reproductive costs and benefits to particular behaviors.

The genetics of primate social behavior.

 

Dominance Status

Dominance has historically been a major focus for primatologists, but reanalyses have shown that it can be a bit overrated. (Perhaps early British primatologists studying baboons in captivity saw a mirror of British society... Zuckerman vs. Strum)

Broadly speaking, factors that influence status:

Sex

Age

Aggression

Time in the group

Intelligence and resourcefulness

Motivation

Mother’s social position

 

Primate Cognitive Abilities

Social interactions and problem-solving abilities demonstrate primate intelligence.

The fact that apes can’t speak has more to do with their anatomy and the language related structures of the brain than intelligence.

They do have communication systems, and our understanding of these is constantly developing.

Primate Sounds: http://www.monkeymania.co.uk/gosounds/

Koko the gorilla: http://www.gorilla.org/world/daily.

Koko meets Mr. Rogers: http://ali.apple.com/ali_sites/ali/exhibits/1000790/koko_meets_the_stars.html

http://www.pbs.org/teachersource/scienceline/archives/aug99/aug99.shtm

 

 

Bottom line:  non-human primate studies can contribute to our understanding of human beings, but one should be very careful about the assumptions regarding non-human primates, and even more careful about how the information is used. Simple arguments are usually flawed.

 

ON THE FUTURE OF OUR CLOSEST RELATIVES:

The situation is very severe.

http://news.nationalgeographic.com/news/2004/09/0930_040930_bushmeat1.html,

Great Apes Survival Project: http://www.unep.org/grasp/

Bushmeat: http://bushmeat.net/about.html ,  http://karlammann.com/

 

 

 

Some recent primate research follows.

 

ANDi, the GM Monkey

http://news.bbc.co.uk/1/hi/sci/tech/1112171.stm

 

If you're interested...

 

Fossil Primates - always an adventure!

 

 

Illustration by Kim Reed-Deemer, Northern Illinois University

Reconstruction of a 45 million year old primate, the size of a human thumb! The smallest primate ever discovered.

See below for full story.

 

 

 

 

 

---
 

 

From left to right the primate species depicted on the tree are: a lemur
(Lemur catta), an adapid (Hoanghonius stehlini), a tarsier (Tarsius
bancanus), an omomyid (Shoshonius cooperi), a proto-monkey (Eosimias
centennicus), a South American monkey (Saimiri sciureus), an Old World monkey (Mandrillus sphinx), a great ape (Gorilla gorilla), and a human (Homo sapiens). Inset: new fossil, Eosimias. Full story, below.

 

 

 

 

 

 

 

 

Researchers discover fossils

of tiny, thumb-length primates

 
DEKALB, Ill.—A team of researchers led by Northern Illinois University paleontologist Dan Gebo has discovered the fossils of 45 million-year-old, thumb-length primates.
 
Recovered from the fissure-filled sediments of a limestone quarry in China in 1996, the fossils easily represent the smallest known primates, with one species estimated to have weighed only 10 grams. These distant relatives of monkeys, apes and humans were once the prey of owls, the researchers say.
 
The discovery of the smallest primates may have widespread implications as scientists plot out the evolutionary family tree leading from lower to higher primates. Living lower primates, also known as prosimians, include lemurs and tarsiers. Living higher primates include monkeys, apes and humans.
 
"Few would have predicted such a diminutive monkey-like creature at such a key branch of evolution," said Gebo, a professor of anthropology at NIU. "These are the smallest primates ever discovered, alive or extinct. Some of these fossils are one-third the size of the living mouse lemur from Madagascar, which at one ounce (31 grams) is the smallest known primate."
 
Gebo’s research team includes Marian Dagosto of Northwestern University Medical School in Chicago; K. Christopher Beard of Carnegie Museum of Natural History in Pittsburgh; and Qi Tao of the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing.
 
Writing in the April edition of the Journal of Human Evolution (London), the team reports on two of the tiny primate fossils.
Estimated to have weighed 15 grams, the larger species is believed to have been a higher primate belonging to the extinct family Eosimiidae.
 
"Both of the fossils are related to a branch of primate evolution that eventually leads to humans," Gebo said.
 
Primates are mammals, characterized by having bigger brains, grasping hands and feet, nails instead of claws and eyes located in the front of the skull. Hundreds of animal fossils, including those of at least three minute primate species, have been culled from a commercial limestone quarry 100 miles west of Shanghai.
 
"The limestone itself is of Triassic age—from the very beginning of the Age of Dinosaurs some 220 million years ago," researcher Christopher Beard said.
 
"The chemical composition of limestone makes this rock dissolve easily in rainwater, leading to the creation of numerous small fissures or limestone caverns that are often much younger than the original limestone itself," Beard added. "As chance would have it, the Triassic limestone in the quarry near Shanghai is crisscrossed by fissures dating to the middle Eocene (some 45 million years ago), in the middle of the interval in which a poorly known lineage of higher primates must have existed."
 
During the middle Eocene, a rainforest occupied the site. However, unlike other prehistoric forests across the globe that had a mix of large and small primates, the Shanghuang rainforest’s fossil record is nearly absent of the larger creatures.
 
"There is no place that mirrors what we’re finding in China," Gebo said. "Other forests in the past have had a few smaller species but they also had lots of big creatures."
 
According to Beard, "The fact that we are sampling a whole radiation of tiny primates at these Chinese sites indicates for the first time that we are glimpsing a part of the evolutionary tree of primates that previously eluded paleontologists."
 
The researchers have no complete skeletons but as many as 50 foot bones belonging to primates weighing less than 100 grams. Markings on the fossils have led the researchers to believe the primates were once the prey of owls.
 
Researcher Marian Dagosto discovered the heel bone of the smallest primate as she sifted through a cardboard box filled with matrix retrieved from the site and processed at the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing.
 
Both Gebo and Dagosto, who in addition to being research partners are husband and wife, are experts in identifying foot bones.
 
"We had literally thousands of bones from all sorts of animals," Dagosto said. "It’s usually a matter of going through them one by one. I found the primate heel bone in the corner of the box, almost under the paper lining. Once I realized just how tiny it was, it did strike me as really odd. I remember calling Dan over right away."
 
Dagosto said the researchers used a statistical technique called regression, comparing the bone size with living animals, to estimate the primate’s size and weight.
 
The researchers say the tiny primates were tree dwellers that relied on a steady diet of insects, fruit and nectar to fuel their high metabolisms. Unlike contemporary higher primates, the tiny primates likely were nocturnal and solitary creatures.
 
"The implication is staggering," Gebo said. "You would think that early higher primates would have a lot of characteristics of later higher primates, which were social creatures that occupied a daytime niche. It probably means we’re getting close to the transition between higher and lower primates."
 
Calling the China site a treasure trove of fossils, the researchers added that 90 percent of the recovered specimens have not yet been analyzed.
 

 

http://www.niu.edu/pubaffairs/RELEASES/2000/MAR/primate/Tinyprimates.htm

 

For more primate information

Primate Info Net  http://pin.primate.wisc.edu/

Bush meat / conservation crisis: http://news.nationalgeographic.com/news/2004/09/0930_040930_bushmeat1.html

New methods of studying primates in the field: e.g. radio telemetry to study ayeayes: http://www.pbs.org/wgbh/nova/kalahari/ayeaye.html

What's in that other 2%? http://www.medicalnewstoday.com/medicalnews.php?newsid=12739

 

More on Pygmy Marmosets

http://www.pbs.org/wnet/nature/gremlins/index.html

http://www.zoo.org/educate/fact_sheets/marmoset/marmoset.htm

http://facultad.usfq.edu.ec/renatol/files/galeria%20foto2.htm

Some skeleton images: http://www.hitchams.suffolk.sch.uk/skeletons/monkey.htm

Chimps
http://www.janegoodall.org/chimp_central/default.

Primate self-medication: http://primates.com/misc/index.html

Gibbon playing with Tiger: http://www.warthai.org/gallery%20pages/gibtiger.htm, 

http://media.hugi.is/hahradi/fyndnar/apetiger.wmv