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 A105 Human Origins and Prehistory
A105 Primate Classification Activity

In this activity you were asked to place a selection of animals, mostly primates, into the best groups you could come up with.  There were a variety of responses.  I've looked at them in more detail, and overall you did a good job -- it's not easy being an amateur biologist confronted with 15 unfamiliar species!  Remember, it took scientists decades to come up with the classification we now accept.  It seems that the root of most difficulties was using a single characteristic -- locomotion -- as either the only classifying trait or as the basis for all further classification. It's always a good idea to look at more than one feature when classifying things, as we'll see when we move into hominids.  Using several features, for instance, would have let you identify the cat as the outgroup (carnivore) as did one team -- for instance, the cat has a very different dental formula, fewer large digits, and a small brain for its body size compared to the primates.  (Incidentally, the team that based its first level on tails vs. no tails -- a single trait -- got lucky, as this separated out the apes.  However, their next level trait (diet) affected their classification the same way locomotion affected the other teams: the diversity of diet and locomotion among primates makes it almost impossible classify them based on just these features, as you found out.  You have to look at the total adaptation :-).

Some further points to remember:
   *The gibbon is an ape, not a monkey. You can tell by its slightly larger brain and body size, and its lack of a tail.
   *Monkeys were the group that probably produced the most difficulty.  In addition to reviewing the information about anthropoids and major monkey groups in the lecture notes, also note this trick for differentiating New and Old World monkeys: count their teeth.  Old World monkeys have dental formulas like apes (2.1.2.3) while New World monkeys have an extra premolar (2.1.3.3) (some, like the golden lion tamarin, have "lost" a molar compared to their relatives).

So, without further ado, here are the classifications of the primates from our activity:

Prosimians: Tarsier, Ring-tailed Lemur, Slow Loris
New World Monkeys: Muriqui, White-throated Capuchin, Golden Lion Tamarin
Old World Monkeys: Black and white Colobus, Hamadryas Baboon, Mustached Guenon, Hanuman Langur.
Apes: White-handed gibbon, Chimpanzee, Mountain Gorilla, Orangutan, technically, Human too.
Outgroup: Cat

Classification of Modern Primates

                           Order  Primates

    Suborder Prosimii 
Superfamilies- Lorisoidea, Lemuroidea, Tarsiioidea   
Lorisoidea: Loris, galago
Lemuroidea: Lemur, indri,
    sifaka
Tarsiioidea: Tarsier

    Suborder Anthropoidea
Infaorder Platyrrhini (New World Primates)
Families Callitrichidae, Cebidae (New World Monkey Families)
Callitrichidae: Tamarins, marmosets
Cebidae: Capuchins, spider monkeys, squirrel monkeys

    Suborder Anthropoidea
Infraorder Catarrhini (Old World Primates)
Superfamily Cercopithecoidea (Old World Monkeys)
Leaf monkeys: Colobus
Other monkeys: Baboon, vervet, macaque, guenon

    Suborder Anthropoidea
Infraorder Catarrhini (Old World Primates)
Superfamily Hominoidea (Apes and Humans)
Families Hylobatidae, Pongidae, Hominidae
Hylobatidae: Gibbons, siamangs
Pongidae: Chimpanzee, bonobo, gorilla, orangutan
Hominidae: Humans

Remember, each taxon contains both living and extinct lineage members.  A more tree-like representation of this classification can be found in your text.