Biology Chapter 5.1 Biodiversity

Quick Review Name 3 ways populations are dispersed. – Uniform, clumped, or randomly What are two ways to keep populations from growing too big, or bringing population size down. – Density-independent factors Weather events; tornados, earthquake, tsunamis, droughts, – Density-dependent factors Disease, predidation (one species killing another), parasites, and competition.

I can… Describe three types of biodiversity. Summarize the direct and indirect value of biodiversity. Explain the importance of biodiversity.

Imagine all the sudden all the rabbits on earth died. What do you think would happen? Would it matter?

Extinction: the disappearance of a species from the biosphere through death. – When a species dies, the health of the biosphere reduces. Biodiversity: The variety of life in an area, which is determined by the number of different species in an area. – Increases the health of the biosphere and stability of an ecosystem.

Three types of Biodiversity Genetic diversity Species diversity Ecosystem diversity

Genetic Diversity The variety of genes or inheritable characteristics that are present in a population. – The different colors of rabbits – A specific color may keep the rabbit safe from predators. – Interbreeding (breeding with a different race or species) can increase a species chance of survival.

Species Diversity The number of different species and the relative abundance of each species in a biological community – Species diversity isn’t equal across the biosphere. There are more of a variety of species in tropical zones than in arctic zones.

Ecosystem Diversity The variety of ecosystems that are present in the biosphere. – The different abiotic and biotic factors in an ecosystem and how species interact in an ecosystem is an example of ecosystem diversity.

The Importance of Biodiversity Why preserve biodiversity? – Direct Economic Value: provides plants and animals that give us food, clothing, medicine, and shelter. Even those species we don’t use are important to the health of species we do. May need genes from species we don’t use for those we do. For example, Teosinte is a relative of corn. It can withstand viral diseases that kill corn. The gene that resists disease was used to engineer corn that can now resists disease. These combining of genes is called genetic engineering.

Indirect economic values: different plants and animals provide us with many important resources. – Oxygen, clean water, nutrients, fertile soil,

Aesthetic value: aesthetic means the beauty. Can we put a value on how a beautiful a grove of trees in the fall are, or the sun shining on a clear lake? Scientific value: Can we put a value on studying something?