Download Processes that drive evolution II

Processes that drive evolution II
Coevolution
Convergent Evolution
Coevolution : Ecological Interactions
When two (or more)species reciprocally affect each
other’s evolution.
(http://evolution.berkeley.edu)
Examples:
Change in plant of any form can result in the evolution of
changes in the herbivores feeding on that plant.
"Leaf Cutter Ant"
Atta sp.
Photo © Steve Kaufman/CORBIS, courtesy Ron Kalasinskas
Predator and Prey: An
‘escalating arms race’
Interaction between predator and
prey is a major force to drive evolution.
Examples:
Toxic rough skinned newt and Garter
snake coevolution.
Cassia Grandis
http://farm5.static.flickr.com/4112/5191
024773_2dac1e4059.jpg
http://ntbg.org/plants/plant_details.
php?plantid=2433
Insect and bird pollinators
Bees and yellow colored flowers
Moths and pale flowers with strong
scents
Humming birds and bright flowers with
recurved petals.
Mutualistic Species
http://biology.clc.uc.edu/co
urses/bio303/coevolution.h
tm
http://www.cas.vanderbilt.edu
exclusive “match” between plants and
insects.
Acacia and ants
Video resource from NatGeo:
http://video.nationalgeographic.com/vide
o/player/kids/animals-pets-kids/bugskids/ant-acacia-kids.html
http://evolution.berkeley.
edu/evosite/evo101/IIIFCo
evolution.shtml
Convergent Evolution: Unrelated species with
similar traits
Process in which two distinct lineages evolve a similar
characteristic independently of one another. This often
occurs because both lineages face similar environmental
challenges and selective pressures.
(http://evolution.berkeley.edu)
Convergent Evolution
Example:
Marsupials in Australia and Placentals in North America.
In class Activity:
CONVERGENCE: MARSUPIALS AND PLACENTALS
Worksheet handouts: Provided in class
http://evolution.berkeley.edu/evolibrary/article/0_0_0/analogy_02