Chapter 4: 4-1 to 4-3

By: Ysabelle BadiangPd #4AP Environmental Chapter 4: Biodiversity and Evolution

4-1

Biological Diversity (Biodiversity): the variety of the earth’s species, or varying life-forms, the genes they contain, the ecosystems in which they live, and the ecosystem processes of energy flow and nutrient cycling that sustain all life; four important components Species Diversity: Genetic Diversity: enables life on the earth to adapt

to and survive dramatic environmental changes Ecosystem Diversity: earth’s variety of deserts,

grassland, forests, mountains, oceans, lakes, rivers, and wetlands

Vocabulary

Functional Diversity: variety of processes such as energy flow and matter cycling that occur within ecosystems as species interact with each other in food chains and food webs

Species: a set of individuals that can mate and produce fertile offspring; ex: Humans- Homo sapiens sapiens

Biomes: large regions such as forests, deserts, and grasslands with distinct climates and certain species adapted to them

Vocabulary

Why Should We Protect Sharks? 400 known species of sharks Range from goldfish-sized dwarf dog shark to

whale shark (18 meters=60 feet) Whale shark, Basking shark, and Megamouth

shark: plant-eating (phytoplankton) 60-75 people worldwide injured and average six

deaths per year (1998-2008) “For every shark that injures or kills a person

every year, people kill about 1.2 million sharks”- (79-97 million shark deaths per year)

Finning: sharks caught for their valuable fins and are thrown back, alive, into the water to drown or bleed to death

Core Case Study

32% of world’s open-ocean shark species are threatened with extinction

Most endangered: Scalloped Hammerhead shark

Around for more than 400 mill. years

Keystone Species: play crucial role in helping to keep their ecosystems functioning

Medical Opportunities: possible cure to cancer and better immune systems Almost never get

cancer and wounds heal without infections

Core Case Study

Have You Thanked the Insects Today?

Sting us, bite us, spread disease, eat our food, invade plants

Lets flowering plants reproduce sexually through pollination

Insects eat other insects= pest control

We need insects more than they need us

Science Focus

Earth’s biodiversity is a vital part of the natural capital that helps keep us alive and supports our economies

Tech: food, wood, fibers, energy (wood and biofuels), medicines

Air and water quality, fertile topsoil, decomposition and recycling waste, and control of species that we regard as pests

Champion of Biodiversity: Edward O. Wilson

Information

Loved bugs as a kid

Specialized in ants

Widened scope to earth’s biodiversity

Theory of island biogeography

First to use “biodiversity” in a scientific paper

Edward O. Wilson

4-2

Fossils: mineralized or petrified replicas of skeletons, bones, teeth, shells, leaves, and seeds, or impressions of such items found in rocks

Biological Evolution (Evolution): process whereby earth’s life changes over time through changes in the genetic characteristics of populations

Theory of Evolution: all species descended from earlier, ancestral species; life comes from life

Natural Selection: individuals with certain traits are more likely to survive and reproduce under particular set of environmental conditions than are those w/out the traits “Biological evolution through natural selection” “Populations- not individuals-evolve by becoming

genetically different.”

Vocabulary

Mutations: random changes in the DNA molecules of a gene in any cell that can be inherited by offspring

Adaptation (Adaptive Trait): any heritable trait that improves the ability of an individual organism to survive and to reproduce at a higher rate than other individuals in a population are able to do under prevailing environmental conditions

Differential Reproduction: enables individuals with the trait to produce more surviving offspring than other members of the population produce

Genetic Resistance: the ability of one or more organism in a population to tolerate a chemical designed to kill it

Vocabulary

Biological evolution by natural selection: “Genes mutate, individuals are selected, and populations evolve such that they are better adapted to survive and reproduce under existing environmental conditions.”

Vocabulary

The fossils found so far represent probably only 1% of all species that have ever lived

Paleontology: trying to reconstruct the development of life with so little evidence; challenging scientific detective game

1858: Charles Darwin (1809-1882) and Alfred Russel Wallace (1823-1913) independently proposed concept of natural selection as mechanism for biological evolution Charles Darwin: On the Origin of Species by

Means of Natural Selection (1859)

3 Successful Adaptations of Humans:Strong opposable thumbsAbility to walk uprightComplex brains

4-3

Tectonic Plates: huge flows of molten rock w/in the earth’s interior break its surface into a series of gigantic solid plates

Earthquakes and Volcanic Eruptions Tectonic Plates Drifting Effects:

Locations of continents and oceanic basins have greatly influenced the earth’s climate and this helped to determine where plants and animals can live

Movement of continents has allowed species to move, adapt to new environments, and form new species through natural selection

Information

Earth is Just right for Life to Thrive

Temperature range: supports life

Orbit size: moderate temperatures

Liquid water: necessary for life

Rotation speed: sun doesn’t overheat surface

Size: gravity keeps atmosphere

Science Focus