Week 3 Notes
Week 3 Notes ENVS 212
Popular in Evolution
Popular in Environmental Science
This 2 page Class Notes was uploaded by Hieu Notetaker on Friday October 16, 2015. The Class Notes belongs to ENVS 212 at Drexel University taught by Dr. Daniel Duran in Summer 2015. Since its upload, it has received 27 views. For similar materials see Evolution in Environmental Science at Drexel University.
Reviews for Week 3 Notes
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 10/16/15
1 Patterns of Evolution a Evolution history and Classi cation Evolution has 2 major features Anagenesis and Cladogenesis Anagenesis gradual accumulation in changes in the characteristics of a lineage over time Cladogenesis splitting of a gene pool into two or more separated pools b Character evolution and Development By mapping characters into a phylogenetic tree we can reconstruct the history of evolutionary changes of a these characters May show that a particular trait has evolved multiple times through convergent evolution One form of convergent evolution is mimicry Batesian mimicry Mullerian mimicry Evolutionary reversals occur when a character state changes from a derived or advanced state back to more primitive state Dollo s Law complex characteristics once lost are unlikely to be regained Mosaic Evolution different characters evolve at different rates Thus a species does not evolve as a whole but rather that its part evolve quasi independently A character state in an organism can be primitive or derived but it is wrong to consider one living species is more advanced than another Individualization a process which organisms evolve distinct identities and specializations for their modules Heterochrony an evolutionary change in the timing or rate of developmental events leading to changes in size and shape Paedomorphosis the evolution of a juvenilelike reproductive adult the retention by adults of traits previously seen only in the young Peramorphosis the evolution of hyperadult features due to extended development Allometry the differential growth of different parts or dimensions of an organism during its ontogeny Simplification of morphology reduction andor loss of structures Very common in module type morphologies c Rates of evolutionary change Adaptive radiations occur when species rapidly diversify to fill available ecological niches Evolution radiation rather than sustained directional evolutionary trends is probably the most common pattern of longterm evolution Futuyma Adaptive radiation can occur because of a key innovation the evolution of a novel trait that enables species to adapt to new environments or lifestyles Different lineages have had very different rates of extinction Pace of evolution gradualism or punctuated equilibrium PE Gradualism large evolutionary changes happen over long periods of time due to many small changes Punctuated equilibrium evolution is sporadic Maj or phenotypic changes occur in a short periods of time Fossil record supported
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'