ARTH 207 Lecture Notes - Lecture 9: Overfishing, Extinction Vortex, Sea Level Rise
12 Aug 2018
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Humans can have direct and indirect impacts on biodiversity. Background extinction account for 90% of extinction so can"t ignore those even if mass extinctions are flashier. Also extirpation can be common (extinction of local population) Can see that most mammals that went extinct were large (over 44kg) Maybe because we hunted larger animals for more food or maybe it was due to a climate change. We do think that humans had to do something with the higher extinction rate in the. Pleistocene since before with just climate change, the extinction rate was still way smaller than what you get when humans are present. Can see a drop in biodiversity in regions after the humans have arrived and it happens very quickly since they have no avoidance behaviour to humans since never encountered some before. Canada has lost 15 animal taxa and 23 species have been extirpated so no longer in some areas in canada.
