ARCL-1006EL Lecture Notes - Lecture 9: Adaptive Radiation, Quadrupedalism, Bipedalism
16 Jun 2018
School
Department
Course
Professor
ARCL 1006
Feb 12, 2018
Primate Evolution
•
•(photo) Relationships between primates
•adaptive radiation: from the photo we can see which points are getting adaptive radiation
•specifically w lemurs, w new world monkeys, old world monkeys, and between ancestors
of strepp and ancestors of haplo
•Adaptive radiation
•where you have a diversification between species//organisms move to new niches
•Generalized trait
•trait that allows for variety of uses//is flexible
•primates limbs- can swing from branches, can be quadrupedal and bipedal
•primate dentition- molars and premolars have rounded cusps and is associated with
omnivore
•advantages: when circumstances change you can easily adapt to those new
circumstances
•Example) if you can move around on and and trees, and the world dries up, you can
still move around on the ground
•Specialized Trait
•Adapted to specific circumstances
•some primates (gorillas) have a specialized diet- leaves
•no leaves= sticky situation
•Tarsiers- long tarsal bones that allow a particular type of locomotion (vertical clinging
and leaping)
•Disadvantage: if no trees, they might have a hard time getting around
•Difficulties faced by palaeoanthropologists
•Discontinuities in fossil record
•space
•fossils are sometimes very well preserved and some not
•time
•different fragmentations of bones
•sexual dimorphism
•might classify different genders as different species
•age related variation
•bones may not be fully formed in juveniles
•pathologies
•Individual variation
•distinguishing homologous from analogous traits
•Homology: human hand VS bat wing //finger bones (evolved from common ancestors)
•Analogy: bat wing VS butterfly wing // adapt to flight// very distantly related organisms
have evolved the same structure on the surface in order to adapt to certain conditions
(not from the same ancestor)
•Are humans more closely related to tarsiers than gorillas because tarsiers have long
legs like we do?
•probably not
