Grade 8: Diverstiy of Life

Diversity of species

what occurs through gradual processes over many generations

fossil records

what provides evidence that changes have occurred in number and type of species

3 results of mutations

1. beneficial for the organism

2.harmful for the organism

3.no effect on the organism

evolution

the process by which populations change over time

4 parts of Darwin's theory of natural selection

1. overpopulation

2. Inherited Variation

3. Selection (struggle to survive)

4. Reproduction

overproduction

part of natural selection where more offspring are produced than will survive

inherited variation

part of natural selection that explains all offspring are different from each other and the parents

selection

part of natural selection where only the best suited organisms survive to adulthood

reproduction

part of natural selection where the survivors pass on their adaptations

Charles Darwin

naturalist who proposed that evolution happens through natural selection

extinct

word that describes a species that has died out completely

species

a group of organisms that can mate with one another to produce fertile offspring

mass extinction

periods of time in which the extinction rates rise abruptly

fossil record

timeline of life provided by the remains or imprints of dead organisms

transitional form

term used to describe parts of the fossil record that are incomplete for an animal's ancestry

DNA, fossil records, comparing inherited traits

what has been analyzed to provide evidence that all animals share a common ancestor

selective breeding

-mating animals so their offspring will inherit desired traits

-process used to change a plant's characteristics to be more productive

adaptation

-change in behavior or physical appearance in response to changes in the environment

-an inherited trait that helps an organism survive and reproduce

natural selection and genetics

modern evolutionary theory includes ideas of _____________and____________

genetics

what did Darwin not know about when he came up with his theory of natural selection

genetic diversity

what increases the likelihood that some individuals will have the characteristics necessary to survive environment changes

antibiotic resistant bacteria

due to increased use of antibiotics in the past , natural selection has caused bacteria that undergo mutation to become resistant to an antibiotic and then survive to increase in number

"The Great Dying"

refers to a large extinction event that took place 250 million years ago causing 90-96% of all animals to go extinct during a short period

characteristics

scientists use these to classify organisms

99%

approximately what % of all life on Earth has gone extinct

ancestor

all species share a common _______________based on comparing organisms DNA

fossils

trace remains of any living organism

natural selection

process by which organisms that are better adapted to their environment survive to reproduce