BIOL 3305 Lecture Notes - Lecture 11: Biological Pest Control, Background Extinction Rate, Permian
Document Summary
Conservation biology: the scientific study of phenomena that affect the maintenance, loss, and restoration of biodiversity. Biodiversity: the variation of life forms in an ecosystem, biome, or the planet. Wild varieties are used to improve cultivated plants. Potential climate change: ecological function, or niches. Species turnover as a result of changes in the ecosystem. Estimate is one extinction every 200 years: mass extinction. These seem to happen every 10 to 100 million years. Late cretaceous (most recent: 65 million years ago (mya, thought to be from metor impact, lost of species. End of triassic: 205 mya, increase in volcanic activity (acid rain, global warming, 48% loss of species. Late permian period: 225 mya, loss of 90% of marine organisms, reasons unknown. Late devotion: 375 mya, occurred in pulses, 50% loss of species, reasons unknown. End of ordovician (latest: 450 mya, 57% loss, reasons unknown, anthropogenic extinction. Rate is 100 to 1000 times greater than background extinction rate.
