Ch. 7 – Biological Diversity Diversity of Life 1. How did it come about? 2. Is it important? 3. What is necessary to sustain that diversity?
7.1 What is biological diversity? - Number of species in an area Within a four mile square area of a tropical rainforest, you would find: Over 750 species of trees 1500 different kinds of flowering plants 125 species of mammals 400 species of birds 100 reptiles 60 amphibians countless insects 150 species of butterflies
7.2 – Biological Evolution Q1/A1 – created by God A2 – Charles Darwin - a change in inherited characteristics of a population from generation to generation(may lead to speciation) - new species arise as a result of competition for resources and differences in an individual’s ability to adapt to the environment
Processes that lead to evolution A) Mutation – change in DNA B) Natural Selection 1. genetic variability 2. environmental variability 3. differential reproductive success 4. influence of the environment on survival and reproduction Ex) mosquitos and resistance to DDT
A Review of DNA
Natural Selection article/bergstrom_02 article/bergstrom_02
Mosquitos and resistance to DDT content/uploads/2014/08/Evolution-of- Mosquitoes-due-to-DDT1.png content/uploads/2014/08/Evolution-of- Mosquitoes-due-to-DDT1.png
Processes that lead to evolution C) Geographic isolation and migration D) Genetic Drift – change in frequency of a gene in a population due to chance 1. Founder effect 2. Bottleneck effect
Geographic Isolation and Migration meline/pangaea#p00fztwb
7.3 – Basic concepts of biological diversity a) Genetic diversity b) Habitat diversity c) Species diversity 1. species richness – total number 2. species evenness – relative of abundance 3. species dominance – the most abundant
Genetic Diversity
Habitat Diversity
Species Diversity/Species Richness es/Animal_diversity_October_ jpg es/Animal_diversity_October_ jpg
Species Eveness ments_of_biodiversity ments_of_biodiversity
7.4 – The evolution of life on earth Slowly Study of fossils Bacteria – changed atmosphere/photosynthesis Multicellular(ocean) Multicellular(land) - gravity - water conservation - gas exchange - moist environment for reproductive system
7.5 – The number of species on earth million named - Estimate million - Table 7.1 p. 127