BI266 Lecture 17: BI266 Biodiversity and Conservation (W7)
Document Summary
Numerous evolutionary radiations occurred during the cretaceous (144-65 million years ago) A major extinction occurred at the end of the period. 85% of all species died in the end-cretaceous (k-t) extinction. For example, passenger pigeons, which numbered three to five billion in the mid 1800s, are now extinct. What is biodiversity": biodiversity is a contraction of the term biological diversity". It was first defined as: the variety of all forms of life at all levels of biological systems (i. e. , molecular, species and ecosystem)". pando is a giant aspen clone in the fish lake national forest, utah. pando is one of the world"s largest organisms. pando is the name given to a clonal stand of aspen trees, all genetically identical and attached to each other by the roots. Extremophiles: these organisms can survive in saturated salt concentrations (36% compared to approximately. Over 15,000 new species are described each year.
