Biodiversity Content PDF
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Uploaded by WellManneredTachisme
Imam Mohammad Ibn Saud Islamic University
Dr.Moodi Al-Subeie
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Summary
This document describes the concept of biodiversity, covering topics such as mutations, natural selection, and different levels of biodiversity. It also examines how biodiversity is measured and distributed across various environments, including altitude and latitude. The document likely serves as lecture notes or educational material.
Full Transcript
(cont.) Where dose biodiversty come from? Dr.Moodi Al-Subeie 1- Mutations ▪ Mutations: the changes in genes (DNA) which code for different traits. ▪ This changes can be beneficial or harmful, or they can have no influence o...
(cont.) Where dose biodiversty come from? Dr.Moodi Al-Subeie 1- Mutations ▪ Mutations: the changes in genes (DNA) which code for different traits. ▪ This changes can be beneficial or harmful, or they can have no influence on survivability. 2- Natural Selection Natural selection operates on the natural genetic variation within a population, selecting for the traits that are most well adapted to the environmental pressures of that habitat. Natural selection Natural selection operates on the natural genetic variation within a population, selecting for the traits that are most well adapted to the environmental pressures of that habitat. Before the industrialization After the industrialization White 100 15 Dark 20 200 Levels of biodiversity Dr.Moodi Al-Subeie Ecosystem diversity Species diversity Genetic diversity (cont.) Levels of biodiversity By: Prof. Faouzi HAOUALA & Dr.Moodi Alsubeie Genetic diversity: ▪ Variety of genes within and between different species. (cont.) Levels of biodiversity Dr.Moodi Al-Subeie Species Diversity: S = 4; N = 15 The variety of species refers to the number of species of plants and animals and the number of individuals in a species (in an ecosystem). (cont.) Levels of biodiversity Dr.Moodi Al-Subeie Ecosystem Diversity: ▪ The variety of habitats natural communities and ecological processes. Measuring of biodiversity 1- Genetic diversity Measured within a population (group of individuals of the same species) or a community (many species). 2- Species diversity (Species richness and species evenness ) -Species richness ▪ The number of different species in an area - Species evenness = 1 ▪ Species evenness describes the relative abundance of the different species in an area. (cont.) Measuring of biodiversity Dr.Moodi Al-Subeie (cont.) Measuring of biodiversity Dr.Moodi Al-Subeie 3- Diversity index: A mathematical expression that combines species richness and evenness as a measure of diversity. The most common measures: Margalef’s Species Richness (d): (S – 1) / Ln (N) Simpson's index (D): Σ (ni / N)2 Shannon's index (H’): - Σ (ni / N) * Ln (ni / N) **************** Patterns in distribution of biodiversty Dr.Moodi Al-Subeie ▪ Biodiversity is everywhere on the Earth. ▪ Biodiversity distribution patterns vary for several reasons: Geographic, Climatic, and Biological. Decrease in species richness with increased altitude االرتفاع Species richness decreases with depth. Species richness decreases with Latitude: The tropical rain forests have more biodiversity than other locations in the world.
