Pre AP Bio -Evolution

Convergent evolution

"side effect" of adaptation radiation, producing unrelated species that look similar to one another.

Lyell

1785 Scientist - 'Father of uniformitarianism' - belief that the earth was old, and catastrophism happened slowly. Earth is shaped by geological forces over a long period of time; estimates Earth is millions of years old. Darwin's response: If Earth changes over time, does life change over time too?

Malthus

1798 Scientist who proposed that organisms reproduce at a faster rate than the environment can support.. If all offspring were able to survive, there will not be enough space and food Influenced Darwin. His response - What factors allow some to survive and others to not survive? There is a struggle for survival due to overpopulation and limited resources.

Lamarck

1809 Scientist who theorized that organisms acquired traits that were needed for survival. First to propose an explanation of how things change over time Tendency Toward Perfection His theory included "Use" and "Disuse" concept - but this concept was not correct.

Wallace

1858 Scientist - Writes to Darwin about Natural Selection because he'd observed the same things in SE Asia that Darwin had seen in the Galapagos Islands.

What is the title of Darwin's book on evolution and natural selection?

1859 Darwin published his book "The Origin of the Species"

Mutation

A change in the DNA; most often harmful, sometimes beneficial.

Population

A group of individuals that belong to the same species, interbreed, have a common gene pool, allele frequency, and live in the same area.

survival of the fittest

A natural process resulting in the evolution of organisms best adapted to the environment.

Temporal Isolation

A reproductive barrier that forms new species when populations begin to reproduce at different times of the year.

Behavioral Isolation

A reproductive barrier that leads to the development of a new species when organisms have different courtship rituals.

Adaptation

Any trait that enhances the survival and reproduction of an organism.

When breeding is controlled to encourage a specific trait.

Artificial Selection

Gradualism

Belief among geologists that organisms evolved through a slow, continuous process.

gene pool

Common group of genes shared by populations. This is where genetic variation of populations is stored.

What is reproductive isolation? Three types? and Examples?

Condition in which a reproductive barrier keeps two species from interbreeding. Behavioral isolation - includes differences in courtship or mating behaviors Ex: different mating songs in birds Geographic isolation - physical barriers divide population. Ex: Fish in the Atlantic can't easily reproduce with Fish in the Pacific Temporal isolation - timing of reproductive periods prevents mating. Ex: 2 species of orchids plants release pollen on different days (can't pollinate each other)

techniques that can be used to analyze DNA and determine these evolutionary relationships.

DNA Fingerprinting Gel Electrophoresis

similar across all forms of life, these molecules provide an excellent way of comparing organisms at their most basic level-their genes.

DNA and RNA

Author of "Origin of Species by Means of Natural Selection"

Darwin

Anatomy as evidence of evolution

Developmental Similarities - Identical or very similar larvae or similar embryos, but result in different adult body forms. ex. of Larvae - Barnacle and Crab Larvee ex. of embryos - alligator, human and chicken embryos all look similar. Vestigial Structures - are remnants of organs or structures that had a function in early ancestors. ex. Ostrich has wings but can't fly. T-Rex can't do push ups and whales have pelvic bones but no pelvis. Homologous Structures - similar in structure but different in function and indicate evidence of a common ancestor. es. Human Hand is similar to mole foot is similar to bat's wing.

Isolation Mechanisms

Factors that affect the gene pool of a population; can lead to the formation of new species

Genetic variation decreases the chances of some individuals surviving - T or F

False - The variations of individuals give some members of the species advantages in the competition to survive and reproduce. Those advantageous traits will be passed to the next generation.

directional selection

Form of natural selection in which the entire curve moves; occurs when individuals at one end of a distribution curve have higher fitness than individuals in the middle or at the other end of the curve. Moves the frequency of an allele in one direction (peak shifts in graph)

Geographic Isolation

Formation of new species when populations have physically barriers that prevent them from reproducing

four types of evidence that support Darwin's theory of evolution

Fossils, geography, anatomy and observation

bottleneck effect

Genetic drift resulting from the reduction of a population, typically by a natural disaster, such that the surviving population is no longer genetically representative of the original population.

Microevolution

Google definition - evolutionary change involving the gradual accumulation of mutations leading to new varieties within a species. minor evolutionary change observed over a short period of time.

Species

Group of organisms so closely related that they can interbreed and produce viable/fertile offspring.

Diploidy

Having a double set of chromosomes; allows for increased genetic variation among members in a population.

The forelimbs of a human and horse are similar but are used for different purposes. What is this an example of?

Homologous structures and Evolution

When a new mutation arises, what determines if that mutated gene will continue to persist in the population?

If it increases the chance of survival.

genetic drift

Is a change in allele frequencies due to chance. - causes a loss of genetic diversity and harmful alleles may become more common - It is most common in small populations. - A population bottleneck can lead to it. It occurs when an event drastically reduces population size. The bottleneck effect is an example of this after a bottleneck event.

Geography as evidence of evolution

Island species most closely resemble the nearest mainland species Also, populations can show variation from one island to another Suggesting that species evolve due to environment

Why is reproduction so important in terms of natural selection and evolution?

It is embedded in the key points of Darwin's Theory of Evolution: individuals of a species are not identical (and cross reproduction occurs); traits are passed from generation to generation (through reproduction); more offspring are born than can survive (high reproduction causes competition for resources); and only the survivors of the competition for resources will reproduce.

Uniformitarianism

Lyell theor - the prevailing theory of geologic change. -Gradual change over time combined with the idea that such changes occurred at a constant rate and are ongoing.

Reasons for extinction

Meteorites, volcanic action, and tectonic plate movement

DNA Sequencing

Most reliable evidence supporting the theory of evolution.

Where are the youngest fossils found, near the surface or deep underground?

Near the surface.

Extinction

Occurs when an organism fails to adapt to changes in its environment. More than 99% of species that ever lived are now extinct

Gene Flow

Occurs when organisms from one community migrate into another; introduces new alleles into the population; can result in a change in the genetic makeup of a population.

If you are a fit individual, you are well adapted to your environment and will produce more ______________ than those who are less fit.

Offspring

Punctuated Equilibrium

Pattern of evolution characterized by long periods of stability interrupted by brief periods of rapid change.

disruptive selection

Population splits into two subgroups (individuals at upper/lower ends of curve have higher fitness)

Fossils

Preserved remains or traces of ancient organisms; used as evidence for evolution

Macroevolution

Refers to large-scale evolutionary pattern and processes that occur over long periods of time.

Darwin

Scientist who believed that organisms with favorable traits survived, reproduced, and passed those favorable traits on to their offspring. Founder of modern evolution theory

Wallace

Scientists who formed identical hypotheses to Darwin; his manuscript prompted Darwin to publish his ideas.

If two different species have similar embryology, then that embryological evidence points to both species having a ___________________ ________________________________.

Shared Ancestor

Embryology

Similarities in the structures of developing embryo of different organisms are considered to be proof of a close evolutionary relationship.

Genetic Drift

Situation in which change in a population's alleles is magnified because the population size is small. bottleneck effect founder effect

Homologous structures

Structures among organisms that have different functions, but are generated from the same embryonic tissue; used as evidence for evolution.

Vestigial structure

Structures reduced in size and function, but may have been used by an ancestor

TL; DR

TL;DR (Too Long; Didn't Read)

Fitness

The ability of an organism to survive and reproduce in its environment.

Descent with Modification

The idea that each living species is related and has arisen (with changes) from other species of organisms over time.

Spicies

The lowest level in the Linnaeus: classification system (kingdom to species) Buffon said species have shared ancestors rather than arising separately

Why is variation important in gene pools in terms of natural selection?

The variations of individuals give some members of the species advantages in the competition to survive and reproduce. Those advantageous traits will be passed to the next generation. Darwin - Some individuals in a species may have a variation of a trait that allows them to survive and reproduce more than others

Fossils as evidence of evolution

These are the remains or traces of organisms that lived long ago. The ones in older layers of the earth are more primitive than those in upper layers of the earth. Suggesting that they evolved over time.

For natural selection to occur, individuals of a population must have different traits/genetic variation - T or F

True - The three requirements for natural selection are 1. Heritability 2. Variation 3. Selective Pressure

Traits must be heritable for natural selection to work on them - T or F

True - The three requirements for natural selection are 1. Heritability 2. Variation 3. Selective Pressure

Bottleneck Effect

Type of genetic drift where a large portion of the population is destroyed by a natural disaster such as a fire, flood, volcano.

Founder Effect

Type of genetic drift where a portion of the population moves to another location; the new population is not necessarily representative of the original population.

Darwin's Theory of Natural Selection

Variation Heritability Overproduction Reproduction Advantage

Biogeography

Variations are seen in the same types of animals based on their environment.

stabalizing selection

When two opposing forces affect the frequency of an allele in a population. (Individuals in center of curve have a higher fitness)

Natural Selection

a mechanism for change that occurs when organisms with favorable characteristics for a particular environment survive

thorns on a cactus, camouflage, antibiotic resistance in bacteria are all....

adaptations

Evolution

changes in a population of organisms over time. ... The change in the characteristics of a species over several generations and relies on the process of natural selection.

Punctuated Equilibrium

characterized with long periods of stability interrupted by brief periods of rapid change. It is controversial but known that evolution does occur at different rates.

divergent evolution

describes evolution toward different traits in closely related species.

Label the image as disruptive, directional or stabilizing

directional

Label the image as disruptive, directional or stabilizing

disruptive

Phylogeny

evolutionary relationships among organisms

What did Darwin observe about Finches in the Galapagos?

finches that live in areas with hard-shelled nuts have strong beaks. Some individuals in a species may have a variation of a trait that allows them to survive and reproduce more than others Darwin proposed that adaptations arose over many generations.

Speciation

formation of new species - a group of similar organisms that breed with one another and produce fertile offspring . . . that is, babies that can make babies!

Cladistic Analysis

identifies and considers only those characteristics of organisms that are evolutionary

Variation

is a difference in a physical trait. Galápagos tortoises that live in areas with tall plants have long necks and legs. Galápagos finches that live in areas with hard-shelled nuts have strong beaks.

artificial selection

is the process by which humans select traits through breeding. - Watch video artificial selection in dogs

Innovations

new characteristics that arise as lineages evolve over time.

Gene Sequencing

reading of the DNA of organisms allow for comparison of the DNA of different organisms to trace the history of genes over millions of years.

derived characters

recent characteristics

Analogous structure

similar function, but there is no evidence of a common ancestor. Comparing cicada to bat. Both have wings but don't have a common ancestor

Label the image as disruptive, directional or stabilizing

stabilizing

Heritability

the ability of a trait to be passed down from one generation to the next. ... If it is close to zero indicates that almost all of the variability in a trait among people is due to environmental factors, with very little influence from genetic differences.

Adaptive radiation

the process where a single species has evolved through natural selection into diverse forms that live in different ways

Coevolution

two or more species evolve in response to changes in each other - can occur in beneficial relationships or in competitive relationships, sometimes called evolutionary - Watch video on coevolution