BIOL 1020U Lecture Notes - Lecture 4: Continental Drift, Ordovician, Devonian
Document Summary
In some cases, biological changes and extinction are correlated with major environment changes which include the following: Climate and temperature: during the last 2 billion years, earth has undergone major fluctuations in temperature. Earth is not uniform, resulting in many different environments. Atmosphere: the emergence of photosynthetic organisms added oxygen to the atmosphere. Land masses: as the earth cooled landmasses were formed creating terrestrial and aquatic environments. The continents have changed shape and separated from each other (continental drift). Glaciation: glaciers have moved across continents and altered to composition of species. It also affects the water level of oceans. Volcanic eruptions: can negatively affect the species near the eruption, causing extinction. When they occur in the ocean, they can form new islands. Massive eruptions can affect global temperatures and limit solar radiation. Meteorite impacts: large meteorites have had substantial impacts on. There have been five major mass extinctions at the end of the ordovician, devonian, permian, triassic, and.
