Chapter 4 ENV Review

Chapter 4 ENV Review - Chapter 4 Evolution Biodiversity and...

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Chapter 4 Evolution, Biodiversity, and Population Ecology Why do we need to understand evolution? To understand how organisms adapt to their environment and change over time It is an essential component of biology and ecology, which are key parts of environmental science o Relevant for agriculture, medicine, pesticide resistance, environmental health No Is there a goal of evolution Evolution The basis for understanding biodiversity Biological evolution Genetic change in populations of organisms over generations. It has resulted in millions of species Natural selection Process by which traits that enhance survival and reproduction are passed on more frequently to future generations vs. those that do not Natural selection What evolution is driven by How natural selection explains patterns in nature Organisms face a constant struggle to survive and reproduce Organisms tend to produce more offspring that can survive Individuals of a species vary in characteristics Some individuals are better suited to their environment and will survive and pass on their genes to their offspring Variations is due to Genes and environments In future generations, genes of Better-adapted individuals will be more prevalent than those of less- adapted individuals Adaptive trait A characteristic that promotes reproductive success in a certain environment Mutations Accidental changes in DNA that may be passed on to the next generations Sexual reproduction Involves mixing of parental genes and leads to genetic variation Recombination Mixing of parental genes The results of natural selection are evident in Each adaptation of every organism Natural selection is shown in lab experiments with Bacteria and fruit flies Adaptive radiation Burst of species due to natural selection Example of adaptive radiation Hawaiian honeycreepers Artificial selection Process of selection conducted under human direction Example of artificial selection Breeders who select only certain individuals by color, size, etc. Breeders have created the great variety of dog breeds and crop plants Selective breeding of animals Exaggerates preferred traits Ancestral wolf what dogs breed derived from Brassica oleracea What cabbage, brussel sprouts, cauliflower, and broccoli derived from Biological diversity Evolution generates this Biological diversity The sum total of all organisms in an area Biodiversity includes Species diversity (# of different species) Genetic diversity Ecosystem diversity Population Group of individuals of a species that live in the same area Species Population or group of populations whose members share certain traits and can
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This note was uploaded on 01/17/2012 for the course ENV 1301 taught by Professor Larrylehr during the Spring '07 term at Baylor.

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Chapter 4 ENV Review - Chapter 4 Evolution Biodiversity and...

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