Biology 1001A Lecture Notes - Lecture 18: Convergent Evolution, Supercontinent, Laurasia
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For example, humans migrated to north america way before, but is a european genetically linked to. Bio 1001a - lecture 18 life on earth. We are in midst of mass extinction, half of current species will be extinct by 2100. But around 18000 new species discovered every year. Dendogramma enigmatica: new species found 1000 metres below sea level, not closely related to anything else, new phylum. Mathematical model for how many species? : estimated 8. 7 million eukaryotic species, some scientists think 8. 7 million is too low, lots of uncertainty. Universal common descent and origin of species: when origin of species published, controversial aspect was the idea that all life (including humans) is descended from common ancestor. Similarities due to descent from common ancestor: most recent common ancestor. Important: not first living thing: only one luca, but many mrcas (most recent common ancestor) One mrca for each group (i. e. bacteria, archaea, eukaryotes, and.
