BIOL 1001 Lecture Notes - Lecture 27: Outcrossing, Ecological Relationship, Carbon Cycle

• School: York University
• Department: Biology
• Course: BIOL 1001
• Professor: Alexander Mills

Document Summary

Adaptive radiation: a major pattern in the history of life, instances of rapid diversification associated with . (b) new morphological innovations (b/c of the new ecological opportunities) Mass extinctions: subjective and artificial concept, have occurred repeatedly throughout the history of life, rapid elimination of most of the species alive in a relatively random manner, rapid extinction. When at least 60% of species present are wiped out within 1 million years: the big five mass extinctions, e. g. background extinctions. Normal loss that always occurs due to : normal environmental change, emerging disease, competition, result from natural selection. Not directly related to fitness or to. The end-cretaceous: 65 million years ago, only 1. 4% of the way back to the start of the earth. Eliminated more than of marine species. The impact hypothesis an asteroid struck earth 65 mya. Caused the extinction of an estimated 60-80% of the multicellular species alive. Evidence : iridium is common in asteroids but not in most earth.