Introduction to Archaeology and Palaeoanthropology:

Humanity's Journeys

Dr. Kathryn Denning

Anth 2140, Sept 2006 - Apr 2007

 24 Oct 2006... Welcome!

Plan for class

1) Announcements

2) Brief recap of macroevolution / the story of life on Earth...

3) Primates... up to about pg. 90 of the text.

Announcements:

Information about Assignment 1, due in tutorial tomorrow.

Reading assignment for next week

Quiz #2 to be held in tutorial Weds Nov 1 at the start of class. 25 minutes long.   Review guidelines are here. We covered some of this last week, and will be covering much of the primate material today in class.

Tomorrow in tutorial: review for quiz

FIRST: RECAPPING FROM LAST WEEK....

Last week, there was a request to review the relationship of DNA to gene to chromosome. Here are some useful diagrams:

The scale of cells etc:

http://www.accessexcellence.org/RC/VL/GG/comparative.html

The Cell, the Chromosome, and DNA

http://www.accessexcellence.org/RC/VL/GG/chromosome.html

The Chromosome, the Gene, and DNA:

http://www.accessexcellence.org/RC/VL/GG/genes.html

DNA structure

http://www.accessexcellence.org/RC/VL/GG/dna2.html

Some other great diagrams are available here: http://www.accessexcellence.org/RC/VL/GG/index.html#Anchor-Genetics-35326

Also from last week...

Locating ourselves in time

See handout.

What are the key dates for biological evolution?  (All dates are approximate!)

And now...

Locating ourselves within the sweep of biological diversity!

Remember... most of the species which have ever existed are extinct!

And remember: We human beings are the result of evolution, but remember the chance events included! There are many moments at which our lineage might have been obliterated, or might just have not developed into us. (see last week)

If you like, visit the Cambrian: http://www.pbs.org/wgbh/evolution/library/03/4/l_034_02.html

Also note: key term: common ancestry -  if two groups evolved from the same earlier group, then they have common ancestry

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Naming species - we use "binomial nomenclature" (Linnaeus) 

Always write as Homo sapiens. Generally, italicize.

Taxonomies are meant to organize diversity in an understandable way, but also to show evolutionary relationships... and so taxonomies develop and change as we learn more about species, either from their forms or from their genetics. (Can't organize according to appearance alone because of convergent evolution, whereby species that are quite separate genetically can look quite similar... e.g. sharks and dolphins are completely different organisms but have some superficial similarities)

(convergence: http://www.pbs.org/wgbh/evolution/library/01/4/l_014_01.html  http://www.pbs.org/wgbh/evolution/library/01/4/l_014_02.html

Human Taxonomy

PRIMATE TAXONOMY

Quiz review question: Be able to fill in the following terms in their correct places on  Fig 3.12 from the Rice book. (On the quiz, the terms would be provided to you in a list.) Primates, Prosimians, Lemurs, Lorises, Tarsiers, Anthropoids, Platyrrhines, Catarrhines, Cercopithecoids, Hominoids, Hominids, Pongids, Hylobatids, Gibbons, Orangs, Gorillas, Chimpanzees, Bonobos, Humans   - You'll review this tomorrow in tutorial.

Another way of classifying the Primates: lemuriformes and lorisiformes together in a new suborder called Strepsirhini, and place tarsiers with monkeys, apes, humans in another new suborder called Haplorhini. Why? Because tarsiers are a little bit closer to anthropoids in their forms and their DNA, than they are to lemurs and lorises.

Similarly... there is much discussion about the precise degree of relatedness between humans and the great apes... and the consequences for correct taxonomy. For example, should it be Homo sapiens, Homo paniscus (rather than genus Pan), Homo troglodytes (rather than genus Pan)... maybe even Homo gorilla (rather than genus Gorilla)?

e.g. Reclassification proponent: www.pnas.org/cgi/content/abstract/1232172100v1

This is not just a matter of genetics but also of philosophy and ethics: would we treat chimpanzees and bonobos differently if they were also "Homo"?

Meet the Relatives.... Your Living Cousins, the Primates!

great galleries:

http://tolweb.org/tree?group=Primates&contgroup=Eutheria

http://www.eskeletons.org/

http://animaldiversity.ummz.umich.edu/site/accounts/pictures/Primates.html

"primate - an order of mammals based on original adaptation to arboreal life including binocular vision and grasping hands. Includes fossil and modern prosimians, monkeys, apes, humans"

230 species of nonhuman primates (and dropping...)

Nonhuman primates are very good at being what they are, i.e. they are not pale imitations of us  -- counter to earlier (religious and secular) notions of us evolving towards perfection, or monkeys being degenerate humans, having fallen from grace

Primate Characteristics (including us!)

Mammals - Placental (i.e. not marsupials or monotremes)

Body hair

Long gestation period with live birth (i.e. not eggs)

mammary glands

varied teeth ( a combination of incisors, canines, premolars, molars)

homeothermy

increased brain size

lots of capacity for learning and flexible behaviour

-overall, not all that specialized

SO more specifically.... WHAT MAKES A PRIMATE A PRIMATE?

* QUIZ review QUESTION: know the basics for the following primate traits in the Rice book pp 84-85: traits 2, 4, 5, 6, 7, 9, 10, 11, 12, 13  (amount of detail needed, for example, trait 4: vision: know that primates have binocular vision, and usually colour vision, and postorbital bars)

Primate Traits - traits that, taken together, distinguish them from other mammal orders:

1. position of foramen magnum (hole for the spinal cord) is on the underside of the skull rather than at the back (cat: http://www.digimorph.org/specimens/Felis_sylvestris_catus/ vs. squirrel monkey: http://www.digimorph.org/specimens/Saimiri_sciureus/338948/  vs. Homo sapiens http://www.digimorph.org/specimens/Homo_sapiens/ )

5.  have bilateral symmetry, four appendages. We have very flexible arms, but somewhat more stable legs.

- that is, we have right and left sides, as well as a top and bottom.

compare to creatures with radial symmetry. http://en.wikipedia.org/wiki/Symmetry_(biology)

3. clavicle allows arms to swing and gives them strength for locomotion or lifting

4. vision is an important sense for primates. most primates today are arboreal; early primates probably were too. Primates have binocular vision and therefore depth perception. Also colour vision. Postorbital bars help frame the eye.

Primate skulls: http://www.digimorph.org/listbysubgroup.phtml?grp=Primate&sort=SpeciesName

6. Most primates use their hands in locomotion. All primates use their hands to manipulate objects. (Humans and chimps have a true precision grip.)

7.  don't smell very well;  they have small snouts and olfactory centres in the brain.

8.  generalized dentition/teeth: incisors, canines, premolars, molars. Old World: 2.1.2.3, New World, 2.1.3.3 

9.  often sit in an erect or semi-erect position, and many are occasionally bipedal.

10.  flat nails rather than claws (except for prosimians, which have claws). They also have pads on the ends of their fingers.

vs. prosimian (lemur) hands http://info.bio.sunysb.edu/rano.biodiv/Mammals/LemurHands.html

11. general diet, i.e. most are omnivores - can digest plant and animal foods

12. brain/body ratio is high. primate brains, relative to their bodies, are larger and more complex, and they have the ability to learn most of their behaviour, i.e. it isn't all simply instinct

13. primates take good care of their infants, which are dependent upon their parents for survival and have to be taught social skills and survival skills.

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