evoch2

• - Species are independently created
• - Species do not change through time
• (similar to Platonic Ideal)
• scientists started to realize this is wrong!

inheritance of acquired characters

selection of the best adapted forms

Nope

Not really. It was actually Wallace who first proposed it to Darwin.

• 1. convince his audience that species changed through time (e.g. demonstrate the fact of evolution)
• 2. provide a mechanism to explain this change (e.g. natural selection)

although people accepted #1, #2 was quite controversial until Gregor Mendel's genetic inheritance work was finally discovered later on in 1900s. Origin of Species published in 1859.

an Austrian monk who bred garden pea plants as hobby and wrote Experiments on Plant Hybridization in 1865 but went unnoticed until 1901 when finally translated into English from German.

named after Gregor Mendel who discovered concepts of genotypes and phenotypes. Known as the Modern Synthesis or moder synthetic view on evolution.

Geology & age of earth (due to discoverance of fossils)

• - observed evolutionary change
• - ring species
• - vestigial features
• - transitional fossils
• - homology

Incidental evolution in response to human activity

bacteria: Alexander Fleming noticed development of bacterial resistance to antibiotics such as penicillin

moths: industrial melanism - peppered moths used to be typically white but due to human industrialism - they became dark colored

bugs: Flat podded golden rain tree introduced to Florida and then Soapberry bugs developed shorter beaks to use the new trees as hosts. Common garden experiments demonstrated that beak length was inherited.

- trait alteration: higher leg bristles selected for on bugs so future generations have more and more bristles.

- behavior: female mice selected for doing more revolutions on wheel so future generations do more and more revolutions

• - domestication of wolves to modern day dogs
• - crop domestication

ring species are evidence of incipient speciation since species are often delimited by the inability to interbreed, but adjacent populations in a ring species can interbreed except for where distantly related populations meet

e.g. Ensatina salamanders