4.1.1 biodiversity

4.1.1 BiodiversityThe variety of life

Biodiversity Whiteboard ActivityA: Everyone will be one type of tree

1. Douglas Fir (Write a D on your whiteb0ard) 2. Walk around and write down 3 peoples names on your board3. Go back to you seat and remain standing4. A disease will now infect one and spread among the trees

B: We will now be different trees (Repeat Steps in A) Douglas Fir (D) Nobel Fir (N) Western Red Cedar (C) Maple (M) Hemlock (H) White fir (W) Lodge Pine (L) White Pine (WP) Western Dogwood (WD)

Important TermsBiodiversity: The

amount of different species living in an area.

Genetic Diversity: Different genetic characteristics of a species. Cheetah populations have

very low diversity, due to inbreeding

Species Diversity: The number of species

or organisms per unit area found in different habitats of the planet.

Important Terms

Important TermsHabitat Diversity: The amount of habitats or

niches in a given areaVariety of forests, deserts, grasslands, lakes,

oceans, coral reefs, wet lands, and other biological communities.

Chaparral Coniferous forest dessert grasslandsdeciduous forest

Biodiversity: Why should we care? Diverse ecosystems are more stable and

more healthyMore resistant to damage from factors like

climate change and spread of diseaseProvides important ecological services to

humansBiodiversity is useful to us as humans

RecreationFood Goods Medicine

Pre-Assessment Questions(Write on Loose leaf paper)

How do you think diversity changes during succession?

Do you think a more complex ecosystem is more or less stable?

How could human activities (agriculture, mining…) impact biodiversity?

What are the potential positive and negative results of human activities that reduce diversity?

How might habitat diversity impact species diversity and genetic diversity?

Ecological Services of BiodiversityFlow of material, energy

in the biospherePhotosynthesisPollinationSoil formation and

maintenance Nutrient cycling Moderation of weather

extremes Purification of air and

water

Important “stuff” From biodiversityFood, fuel, ecosystems, species, fiber, lumber,

paper….90% of all food crops40% of all medicines and 85% of all

antibioticsPacific Yew – Taxol (cancer drug) Willow Tree - Aspirin

Biodiversity of Species

4.1.2-.5 Natural Selection

Darwin Natural SelectionImportant TermsEvolution: A change in the

gene pool of a population over time

Natural Selection: Process by which individuals that are better suited to their environment survive and reproduce more successfully.

Adaptation: An inherited characteristic that increases an organism’s chance of survival.

Darwin's Research

Studies 13 species of finches on Galapagos Islands

Looked a beak size and shape:Stout beaks for eating seedsShort and sharp beaks for

eating insects.Woodpecker-like beak for

eating insects from trees, but instead of a long tongue it uses a cactus spine held in its beak to remove its prey.

Darwin’s Finches

Darwin’s Theory Based on his observations he

proposed that the evolution of species occurs by Natural selection.

Occurred due to:Variation within populations

(Genetic Diversity) Overproduction of offspring (J and

S curves) Struggle for existence

(Competition/ Limited resources)Unequal survival and reproduction

rates (R and K)

Survivors reproduce more successfully.

Mutations & Sexual Reproduction produces variations among offspring.

Population changes over time.

Limited resources leads to a struggle for survival between offspring.

Overproduction of Offspring

Population of Organisms

What is a species? Species: A group of interbreeding

populations, with a common gene pool, which are reproductively isolated.

It’s not all about looks!

Western Medowlark Eastern Medowlark

Different Species:They do not Interbreed, because they have different songs.

What is a species…Species definition was

made by humans, and fails to fully define nature.

These two ants look different are the same species of ant fulfilling different roles in a colony.

Pheidole barbata

Species definition is not always black and whiteAre we the same?

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ZONKEY

Photo: Wiki Commons/GNU

Are we the same?

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LIGER!

Speciation due to isolationThe islands are close

enough to allow migration and cause distinct island populations to arise.

But the distances between the islands is great enough to reduce interbreeding between islands

This has made possible the formation of distinctive species on the islands

Speciation in grand canyon

Speciation occurred on the earth over a very long period of time when the continents slowly drifted apart.

This leads to geographic isolation

Speciation of salamanders due to geographic isolation

Process of Natural SelectionOrganisms became isolated on various

continents which restricted interbreeding populations

Without the opportunity to interbreed and the slowly changing climatic conditions organisms “evolve” into a new species over time.

This leads to “survival of the fittest”Fitness: Organisms that are better suited to

survive and reproduce

Discussion Question Why does Australia have such strange

animals??

Evolutionary Timeline of mammals

Platypus (Monotreme)Kangaroo (Marsupial) Dingo (Placental Mammal)