Learn: Evolutionary Medicine Exam 1

Lyell

-wrote principals of geology which darwin read

-He stated that geological processes are continous

Linnaeus

- wrote about the first heirachal classification of organisms

- noted morphological similarities between closely related species

- believed that species were static and created by divine intervention

- treated fossils as organic compounds

Erasmus Darwin

- Charles Darwins grandpa

- talked about how species could mutate

- recognized transformations but didnt have a mechanism for evolution

- was the first to propose the origin of species through evolution

Lamarck

-he had the idea that constant use of an organ or trait strengthens and enlarges it

- inheritance of acquired characteristics

- all changes from the influence of enviorment are passed down to offspring

- lineages originate spontaneously then evolved through the influence of vital fluids

Malthus

- wrote essays on the principal of population

- talked about how populations grow exponentially while resources grow arithmetically.

Wallace

- did work in the malay archipelago

- independently came up with the theory of natural selection in 1858

Evolutionary Fitness

the ability of an organism to survive and reproduce, passing its genes to the next generation relative to others in its population

Exaptation

use of a trait for a novel purpose other than its adaptive purpose, results from co-expression with trait that was selected upon

Red Queen Hypothesis

a form of coevolution that allows hosts to evolve at a rate that counters the rapid evolution of parasites

Natural selection

-the survivability of adaptations that increase the ability of an organism to survive

- its non random selection with differential survival and reproduction any one organism in a species will differ from another with these differences changing across generations.

- organisms produce more offspring than an enviornment can support with each offspring having a variance and only the best suited variances will survive

sexual selection

- males and females expand different amounts of energy in producing offspring

- females are limited by nutrients while males are limited by # of females

- the outcome is favoring traits that improve reproductive success

3 mechanisms for sexual selection

1. Mate choice- females are choosier when picking a mate because females expend more energy on rearing offspring.

2. intrasexual competition- usually male-male results in differential reproductive success forcing natural selection

3. intersexual coercion - often males forcing females this gives the male an increased chance of siring offspring

Handicap Principal

- the degree of handicap= degree of benefit

- when a female is able to evaluate a males probability of survival based on traits that are hard to fake or their handicap or degree of showiness

Good Genes Hypothesis

the theory that animals will choose mates for genetic disease resistance by selecting a mate with a costly trait. such as long tail or bright feathers. trait that are hard to fake but are assumed to be indicators of good health

life History Theory

- part of evolutionary ecology that attempts to explain phenotypic evolution

- mathematical description of the frequency and timing of events from birth to death

7 traits of life history theory

1. size at birth

2. growth patterns

3. age at maturity

4.size at maturity

5. #, size, sex ratio of offspring

6. age ad size specific mortality

7. length of life

phenotypic Correlation

- statistical measure of how strongly the values of 2 or more traits vary together in a population.

- things that effect this are demopraphy, bet hedging, tradeoffs, lineage specific events, as well as quantitative genetics and reaction norms

reaction norms

the interaction between genotypes and the environments to create phenotypes

phenotypic plasticity

- the occurrence of phenotypic variation of a single genotype interacting with different environments allowing for a range of different phenotypes to be expressed

- a trait that if altered affects fitness, physiological, morphological, and behavioral

Adaptation

- the ability ot adapt to different enviornments with a range in variation in the phenotypes

- its hard to identify an _____ because first you have to define it then you have to identify the fitness benefits of the trait