Species Diversity

1. Species Diversity

2. Classification • In order to understand how diverse this world is we as humans needed to group up all the organisms on earth. • Classification is the process of grouping. • Using similarities and differences in physical characteristics to sort all things. • Taxonomy is the study of classification of organisms.

3. Classification • All organisms on earth are put in to categories. Those categories are the basis of classification. • There are 3 Domains: • Bacteria • Archaea • Eukarya

4. Classification • The 3rd domain is further broken down into 4 more categories (kingdoms). • Eukarya: • Protista • Fungi • Plantae • Animalia

5. Classification • We classify organisms by looking at similar or different physical traits. Dichotomous keys are used to group organisms. • Activity: Pamishan Creatures • Using the dichotomous key, find the taxanomic name for each creature

6. Diversity • Knowing how to classify and organize different organisms will help in finding out how many different types of organisms we have on earth. • Biodiversity is the variety of species we have on earth, all the genetic information they carry and where they live that makes them unique. • Species diversity – The amount of and types of species that live within a community. • Genetic diversity – the variety of genetic information that can make up one type of species. • Habitat diversity – All the different types of ecosystems, communities and areas that a biome can have within it.

7. Simpson’s Diversity Index Diversity Index: An estimated quantitative measurement of how diverse a species is or the abundance of species within an ecosystem. Simpson’s diversity index: Measures both species richness (number of…) and species evenness (abundance) D = N(N-1) ∑ n(n-1) N = total number of organisms of all species. n = total number of organisms of one species. D = 1 lowest diversity, D = <1 higher the diversity

8. D = 1- ∑ n(n-1) N(N-1) A second way to analyze the diversity index. 0 < D > 1 Less diverse More. The inverse of the other equation. Simpson’s Diversity Index can be expressed either way. I have seen this version used more frequently than the other one.

9. Diversity Index Activity: remember the “environments” from predator/prey simulation? Let’s look at them again. We are explores to a new area. We want to know how many species we will be in contact with and how many there is of them. (species richness and evenness). • On a piece of paper categorize your new found environment. • Look at your environment and identify (give names) to the organisms that live in it. • Count the number of different organisms you can find. • Count how many you have of each organism. • Apply the Simpson’s diversity index formula to determine your species diversity.

10. Geological Time Scale • Earth was formed approximately 4.6 bya. • First life forms: • single cell/bacterial like organisms. • lived in aquatic environments. • 65 mya – dinosaurs became extinct. • ~200,000ya Humans were first seen on earth. • Humans are relatively young on the time scale compared to some of the other organisms still living today. • ex: turtles/alligators

11. Geological Time Scale • There were approx. 5 mass extinctions that have taken place over the life of the earth. • The most famous mass extinction is the K-T extinction. Or Dinosaur extinction. • ~65 mya the dinosaurs disappeared from earth. • Most believe it did not happen overnight (widely debated a decades ago), but over a long period of time. Many thousands of years.

12. K-T stands for Cretaceous-Tertiary. Occurring during the Cretaceous and Tertiary Geological periods of time. • Most today believe that the change in climate caused a mass extinction of the land and ocean large animals and the small plankton. Most small animals including the growing diversity of small mammals, and plants survived. • The change in climate was from a meteor hitting the earth in the Yucatan Peninsula of what is today known as Mexico and the volcanic unrest of Deccan Plateau of what is known as India today.

13. The change in climate was caused by the natural disasters of that time. • The disasters caused the sun to disappear behind the haze of smoke and particulates in the atmosphere. • This caused photosynthesis to lessen and many plants to die off or shrink in size to survive. Which in turn caused less food for the plant eaters and less plant eaters for the meat eaters. And so on. (positive feedback) • This also caused a change in temperature which most larger animals could not handle.

14. Geological Time Scale • Let’s build! • We are going to build our very own time scale. • Include: • ~ years and name of Eras and Periods of time • Mass extinctions with ~time and estimate of loss of species. • Which organisms proliferated and which era/period time • Be Creative! And use color. • Use the scale on pg 94 of the companion book and 284 of APtxtbk as examples.