Chapter 4 Review Kelsey Locklear April 28, 2014 1st
4.1 What is Biodiversity and Why Is It Important? • Biodiversity Is a Crucial Part of the Earth’s Natural Capital • Biological diversity or biodiversity is the variety of the earth’s species or varying life-forms, the genes they contain, the ecosystem in which they live, and the ecosystem processes of energy flow and nutrient cycling that sustain all life. • Species is a set of individuals that can mate and produce fertile offspring. • Every person or organism is categorized in their own species of which has its own traits. • Many species of the Earth are not yet discovered. There is a prediction of about 10 to 14 million different types of species.
4.1 What is Biodiversity and Why Is It Important? • Biodiversity • Species diversity- most obvious • Genetic diversity- allows adaption to survive • Ecosystem diversity- earth’s variety of deserts, grasslands, forests, mountains, oceans, lakes, rivers and wetlands (classified as biomes) • Functional diversity- the variety of processes
4.1 What is Biodiversity and Why Is It Important? • Earth’s biodiversity is very important, it keep us humans alive and it also supports of economies. • Biodiversity can produce many things with the help of technology • Food, wood, fibers, energy from wood and biofuels, and medicines • Biodiversity can also help with the quality of our air and water, maintaining fertile soil, decomposing and recycling waste, and controlling populations.
4.2 How Does the Earth’s Life Change over Time? • Biological Evolution by Natural Selection Explains How Life Changes over Time • Ancient life can be discovered through fossils found in rocks and drill core samples from glacial ice. • Theory of evolution is all species descended from earlier, ancestral species • Basically life comes from life • Charles Darwin and Alfred Russel Wallace proposed natural selection as a way for biological evolution to occur. • Natural selection- individuals with certain traits are more likely to survive and reproduce under a particular set of environmental conditions than are those without the traits. • Biological evolution through natural selection is the reason behind how life changed over the pass years and why is so different today.
Evolution by Natural Selection Works through Mutations and Adaptations • Biological evolution by natural selection involves changes in a populations genetic makeup through successive generations • Populations not individuals evolve by becoming genetically different • Step 1: the development of genetic variability • Occurs through mutations of a gene in any cell that can be inherited by offspring • Step 2: natural selection • Occurs when the heritable trait leads to differential reproduction • The process of biological evolution by natural selection can be summarized as genes mutate, individuals are selected, and populations evolve
Adaptation through Natural Selection Has Limits • Is it possible that through natural selection we are becoming more adapted to the environmental conditions? • This is incorrect because • 1st there is a beneficial heritable trait in a population • 2nd even if the beneficial heritable trait was present the reproductive capacity would limit the populations ability to adapt.
Three Common Myths about Evolution through Natural Selection • Misconceptions about biological evolution through natural selection • One- “survival of the fittest” • Two- organism would develop the traits because of their need • Three- a grand plan would become
4.3 How Do Geological Processes and Climate Change Affect Evolution • Tectonic plates can have important effect on evolution and distribution • 1st location can influence the climate and the organisms in a certain place • 2nd species have moved from continent movement and they have adapted to the changes • New species were also formed
4.3 How Do Geological Processes and Climate Change Affect Evolution • The climate change of cooling to heating could have caused • Advancement of ice sheets at high latitudes • And also retreat of them • These types of climate changes could be major and have a big effect on the types of plant and animals in that area • Some species could not keep up with the climate change which caused a species extinction
4.4 How Do Speciation, Extinction and Human Activities Affect Biodiversity? • New species can be made from natural selection which is called speciation • Sexual reproduction is the main way for this evolution to occur. • This type of evolution can occur over hundreds of year
4.4 How Do Speciation, Extinction and Human Activities Affect Biodiversity? • Once extinction is done it is forever. • There is also many type of extinction • Extinction could be caused by multiple reasons such as starvation, or climate change.
4.5 What Is Species Diversity and Why Is It Important? • Species diversity is the number and variety of species it contains. • Species diversity is important because • The more species there is the more there is to study • More species means more organisms as in bacteria, virus • The more species there are the more secrets the world holds
4.6 What Roles Do Species Play in an Ecosystem? • Each species has its own role • Their role is played where they inhabitant • The five major roles the species can play in a ecosystem is • Native • Nonnative • Indicator • Keystone • Foundation species
Chapter’s three big ideas. • Populations evolve when genes mutate and give some individuals genetic traits that enhance their abilities to survive and to produce offspring with these traits (natural selection). • Human activities are decreasing the earth’s vital biodiversity by causing the extinction of species and by disrupting habitats needed for the development of new species. • Each species plays a specific ecological role (ecological niche) in the ecosystem where it is found.