Biology Unit 8 - Evolution

Fossils, Homologous Structures, Vestigial Organs, Embryology

any remains, impression, or trace of a living thing of a former geologic age, as a skeleton, footprint,etc.

an example of an organ or bone that appears in different animals, underlying anatomical commonalities demonstrating descent from a common ancestor.

A rudimentary structure in humans corresponding to a functional structure or organ in ancestral animals.

the branch of biology and medicine concerned with the study of embryos and their development.

any inherited characteristic that increases an organism’s chance of survival.

organisms that can produce fertile offspring when mated naturally.

a group of individuals of the same species in a defined area who interbreed.

Living things have changed over time, All species were descended from other species, Organisms were somehow adapted to their environments.

Lamarck proposed that by selective use or disuse of organs, organisms acquired or lost certain traits.

No. August Weismann disproved Lamarck’s theory by cutting the tails off of 20 generations of mice. As all of the rest of the generations, the 21st generation of baby mice still had tails.

Because he helped Lamark discover if his theory was correct.

a scientist that founded natural selection

He founded natural selection in evolution which means that all animals came from one species

No. If the human race continued to grow unchecked, sooner or later there would be insufficient living space and food for everyone. The only forces he observed that worked against this growth were war, famine, and disease.

He said that it would decrease.

It helped Darwin continue his process in discovering if his theory is correct and seeing if natural selection was correct.

It explained how geological phenomena occurred over long periods of time.

Fitness, Adaptation, Survival of the Fittest.

Genetic variation exists, Environments vary and present different challenges, .Organisms produce offspring in abundance. (competition for resources), Some individuals are better adapted by chance, Those individuals best suited to the environment become dominant in that population leaving more offspring.

The enviornment

Physical barrier between a population may eventually produce 2 different species, Mating habits (ie: frogs)

the formation of new and distinct species in the course of evolution.

an organism's ability to survive and reproduce in a particular environment.

the situation where different species may live in the same area, but properties of individuals prevent them from interbreeding.

the breeding of plants and animals to produce desirable traits.

Natural Selection, Mutation, Genetic Drift, Gene Flow (Migration).

a permanent, heritable change in the nucleotide sequence in a gene or a chromosome.

If it causes an improvement in fitness of the individual, then the gene will be passed onto future generations.

It’s a part of the species that contain new genes, which makes the next generation lucky (not necessarily better). EXs: The Bottleneck effect, and the Founder Effect

When there is a drastic reduction in population the surviving individuals may have a different allele/gene frequency than the original population.

a few individual from a population start a new population with a different allele/gene frequency than the original population.

the transfer of alleles or genes from one population to another.

It’s responsible for a marked change in allele frequencies (the proportion of members carrying a particular variant of a gene).

the action or process of mutating.

Variation in the relative frequency of different genotypes in a small population, owing to the chance disappearance of particular genes as individuals die or do not reproduce.

When there is a drastic reduction in population the surviving individuals may have a different allele/gene frequency than the original population.

the loss of genetic variation that occurs when a new population is established by a very small number of individuals from a larger population.

the transfer of alleles or genes from one population to another.

It shows relations among organisms.

It is to help you see what genetic traits any species or organisms contain.