Unit 5 APES - Evolution/Biodiversity

Cells

Basis of life on earth

Prokaryotic

No nucleus

Eukaryotic

Has nucleus

Taxonomic Hierarchy

Phylum, class, order, family, genus, specific name

Species

Organisms with the potential liability to produce fertile offspring

Chemical Evolution

Formation of earth, small molecules form, large organic molecules form, protocells form

Evidence of the Past

Fossil Records, radioactive dating, DNA, Ice/Mud cores

Evolution

Change in the genetic makeup of a population through successive generations

Nucleotides and DNA

Carry genetic information

Genes

Sequences of DNA that code for traits

Gene Pool

Population’s collection of genes

Alleles

Different forms of a gene, randomly shuffled during sexual reproduction

Mutation

Random change in the DNA structure of an individual

Mutagens

Chemicals and energies that cause mutations

Gene Flow

Genes moving between populations

Natural Selection

Occurs when traits enable some individuals to survive and produce more offspring

Step 1 of Natural Selection

Requires heritability and variability

Step 2 of Natural Selection

Reproductive advantage, ability to leave more offspring

Step 3 of Natural Selection

Advantageous alleles increase in frequency in successive populations

Step 4 of Natural Selection

Selective Pressure - environment conditions that lead to the possibility of mutations being beneficial

Adaptive Trait

Beneficial mutation

Directional Natural Selection

Allele frequencies at one end of the range of variability to become more prevalent

Stabilizing Natural Selection

Eliminates individuals on the extremes of variability

Diversifying Natural Selection

Extremes are favored and the average is eliminated

Co-evolution

Different species evolve together

Fundamental vs. Realized

Potential vs. Reality

Generalist

broadly adapted

Specialist

Specific need

Convergent Evolution

similar ecosystems and selective pressures

Speciation

When natural selection leads to the development of 2 species from one

Extinction

When a species is permanently lost

Background Extinction

Low and slow

Mass Depletion

In the middle

Mass Extinction

Up to 70% species go extinct over a few million years

Adaptive Radiation

Rapid evolution of numerous new species to fill the void created by mass extinctions

Island Species

Specialists

Biodiversity

Variety of genes in a population

HIPPCO

Habitat loss, invasive species, population, pollution, climate change, over-exploitation

Fragmentation

occurs when large area of habitat is broken into many smaller, more isolated areas of habitat

Edge Habitat

Habitat on the edge of a forest split

Fragmentation Causes

Road ways, agriculture, logging

Ways to Reduce Biodiversity Loss

Criminalize poaching, sustainable land managment, restore habitats, protect land, corridors

CITES Treaty

Bans the hunting, capturing and selling of ES or their parts/products

ES Act

Illegal to hunt ES, sell buy ES products, damage critical habitats of ES