BIOL 2040 Lecture Notes - Lecture 2: Reticulate Evolution, Anagenesis, Cladogenesis
3 May 2018
School
Department
Course
Professor
Evidence for Evolution
September 15, 2015
1. Theoretically possible histories of life
• at each fork new organisms arose from existing organisms = cladogenesis
• reticulate – net-like
• only evidence for evolution is eukaryotes is anagenesis and cladogenesis
• through lateral gene transfer in prokaryotes, there is evidence of reticulate
evolution
Possible Histories of Life:
a) Special Creation
b) Descent with modification
*TEFF: tetrapods evolved from fish
2. Evolution in Action
• Biston betularia – the peppered moth
o has 2 forms: nonmelanic & melanic (darker)
o In 1848 Manchester, UK, black form apparered
o In polluted regions there is less lichen and therefore, the moth become more
black
o Later the pollution declined
o A recent selection study released 4864 moths and found strong selection
against melanic
• House Sparrows
o Introduced to USA in 1850s
o Their population expanded to an extreme amount across the United States
o Since introduced, it has evolved into different sizes in various regions
▪ Smaller in the south, larger in the north
• Bushy_tailed Woodrat (only native rat in Canada)
o Body size could be estimated from fecal pellets in paleomiddens over past
25000 years
o Body size decreased during periods of warming (Bergmann’s Rule)
Special creation Special creation
& Anagenesis
Anagenesis &
Cladogenesis
Reticulate evolution
Special creation
w/
Anagenesis &
Cladogenesis
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
September 15, 2015: theoretically possible histories of life. Cladogenesis reticulate (cid:498)net-like(cid:499: at each fork new organisms arose from existing organisms = cladogenesis, only evidence for evolution is eukaryotes is anagenesis and cladogenesis through lateral gene transfer in prokaryotes, there is evidence of reticulate evolution. Possible histories of life: special creation, descent with modification. *teff: tetrapods evolved from fish: evolution in action, biston betularia the peppered moth, has 2 forms: nonmelanic & melanic (darker) In polluted regions there is less lichen and therefore, the moth become more black: later the pollution declined, a recent selection study released 4864 moths and found strong selection against melanic, house sparrows. 25000 years: body size decreased during periods of warming (bergmann"s rule, evolution of resistance of azt of hiv cells, microevolution from selective breeding, choose specific trait to bred for, ex. Selective breeding in wolves and dogs: ex.
