Warm Up 4/15 Finish Hunger Games graphs Answer these questions on your graph paper: – What did you observe about the population size of the flat runners after several generations? – What did you observe about the population size of the high hoppers after several generations? – What 4 factors influenced the population size of the consumers? Read pg E 25 about “Natural Selection”

Biodiversity & Species SWOD: Natural Selection

Biodiversity The number of different species in an area Biodiversity = a variety of animals and life

The value of biodiversity 2 ways: 1. economic value – Foods, resources, commodities -Medicines 2. ecological value – Food webs

Concerns with Biodiversity Decline in habitat  Extinction/endangered species (extinction = organism is completely gone (endangered = very few species left and could possibly become extinct)  Causes: watch video and write down all the causes of extinction.

Extinction Causes  Causes: 1.Habitat destruction (primary cause) 2.Poaching 3.Pollution 4.Exotic species

Thylacine

Exotic Species Also known as introduced or invasive species -Means: a non – native species that has been introduced to an ecosystem -Usually results in negative effects to the food web

Introduced/Exotic species Advantages: Pollination Food – Butterflies feeding on non-native plants Reforestation – Exotic trees restore forest to help bring back native species Endangered

Examples of Exotic Species that were harmful Zebra Mussel Kudzu Nutria Rat River Monster & Piranas

Zebra Mussels

Disadvantages 1. Kudzu: prevent soil erosion Kudzu video

Nutria Rat