Evolution of Organisms: Review Flashcards

A set of flashcards designed to help review key concepts related to the evolution of organisms and their behaviors.

Evolution

The change in the gene (allele) frequencies in biological populations over time.

Development

The process by which organisms grow and develop from a single cell into a complex organism.

Genotype

The genetic constitution of an individual organism.

Phenotype

The observable physical properties of an organism; these include the organism's appearance, development, and behavior.

Fitness

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

Neofunctionalization

A process where duplicate genes evolve new functions.

Subfunctionalization

A process where duplicate genes evolve to share the original function between them.

Gene duplication

A process where a gene is copied, resulting in two copies of that gene in the genome.

Genetic redundancy

extra gene copy that can undergo change without much consequence

Promiscuous proteins

likely to take on new functions after duplication

Ontogeny

The development of an individual organism from fertilization to adult form.

Phylogeny

The evolutionary history and relationship among a species or groups of species.

Evo-Devo

A field of biology that compares the embryonic development processes of different organisms.

Homeotic Genes

Genes that control the body plan of an embryo along the head-tail axis.

Hox genes

A group of related genes that control the body plan of an embryo along the anterior-posterior axis.

Heterochrony

An evolutionary change in the timing or rate of developmental events.

Paedomorphosis

A form of heterochrony in which descendants retain juvenile characteristics of their ancestors—reduction in the rate of change of development.

Peramorphosis

A form of heterochrony where descendants exhibit traits that are more developed than those of their ancestors— Increase in rate of change of development.

Isometric growth

A pattern of growth in which all parts of the organism grow at the same rate. A linear change.

Allometric growth

A pattern of growth in which different parts of the organism grow at different rates.

Allometry

The study of the relationship of body size to shape, anatomy, physiology, and behavior.

Developmental constraints

Limitations on the evolution of morphology and behavior due to the way rules of development are structured.

Evolutionary Stable Strategy (ESS)

A strategy that, if adopted by a population, cannot be invaded by any alternative strategy.

Kin selection

The type of natural selection that favors behaviors that help relatives.

Reciprocal altruism

Altruistic behavior towards unrelated individuals with the expectation that the favor will be returned.

Cooperative behavior

Actions by individuals that benefit other members of the group.

Manipulation

Behavior that appears altruistic but is actually selfish, benefiting the manipulator.

Mutualism

A type of interaction between organisms in which both parties benefit.

Prisoner’s Dilemma

A standard example of a scenario in which cooperation or defection can be analyzed.

Convergent evolution

The independent evolution of similar features in species of different lineages.

Divergent evolution

The accumulation of differences between groups which can lead to the formation of new species.

Speciation

The evolutionary process by which populations evolve to become distinct species.

Altruism

A behavior that benefits another at the cost to one’s own survival and reproduction.

Belding's ground squirrel

A species known for its alarm calling behavior, which is considered an example of kin selection.

Hamilton’s Rule

A principle stating that a gene for altruistic behavior will spread if the benefit to the recipient multiplied by the relatedness of the recipient to the altruist exceeds the cost to the altruist.

Eusociality

A type of social organization characterized by cooperative brood care, overlapping generations, and division of labor.

Inclusive fitness

The total number of offspring an individual can produce, plus the number of offspring of its relatives they help to rear.

Orthologous

genes that have evolved from a common ancestral gene and retain similar functions across different species.

paralogous

genes that have arisen by duplication within a genome and may evolve new functions. Within one species.

Co-linearity

The concept that the order of genes on a chromosome is preserved across different species, indicating evolutionary relationships.

MADS genes

A family of genes scattered through the genome, involved in the regulation of flowering and the development of various plant organs such as flowers and fruits. They are characterized by a specific DNA-binding domain known as the MADS-box, which plays a crucial role in angiosperm development.

Heterotropy

Tweaking the location of expression of developmental genes can strongly impact the phenotype.

Darwins Demon

Born mature

reproduces immediately

reproduces infinite number of offspring

lives forever

Darwin’s Dolt

delays maturation

reproduces asexually (clones itself)

one offspring that does not disperse

delays reproduction and died immediately after

Senescence

The gradual deterioration of functional characteristics in organisms as they age, leading to increased mortality and decreased reproductive success.

constraints"— rate of living theory

aging is due to genetic and physiological constraints that limit biological processes and energy use in organisms.

evolution: evlutionary theories

aging is a result of evolution: trade-offs of reproduction versus repair

RLT- accuculation of damage to cells caused but errors in…

• Replication

• transcription

• translation

• purging metabolic by-products

Rate of living theory predictions

1. As cell damage results from metabolic by-products, the aging rate and metabolic rate should be positively correlated.

   1. Metabolic rates and aging rates are NOT correlated

   2. Austad and Fisher (1991): Energy expenditure per lifetime varies greatly, even within closely-related groups

2. There is no genetic variation for further repair— it should not be possible to select for longer life spans through natural or artificial selection

   1. luckinbill et al. (1984): longevity increases dramatically. No big differences in metabolic rate between lines, genetic variance for repair and longevity

Telomere

A repetitive section of DNA at the end of a chromosome, important for cell division. Cancer and germ-line cells have strong expression of telomerase. 

Progressive degradation of telomere may result in senescence. 

senescence: evolution theory of aging

aging caused by incomplete repair of cell/tissue damage. This theory offers two explainations

1. accumulation of deleterious mutations

   1. affect organisms later in life

2. trade-offs between reproduction and repair (antagonistic pleiotropy)

   1. selection for pleiotropic genes that are beneficial in early life and costly in later life

what types of genes could have pleiotropic effects?

gene that allocates less energy to repair and more to reproduction early in life

trade off between investment in sex versus longevity in crickets?

• high quality females (consuming high protein) lived longer

• high quality males (high protein diet) lived shorter BUT called more— trade off between increased reproduction and decreased longevity

  • during their lifetime, high-protein mlaes called more than low-protein males

Kolora et al, 2021: life history evolution in rockfish

• much of lifespan can be predicted by body size and depth

• compared long and short-lived species to look for signatures of selection in the genome

• butyrophilin gene duplications

• immunoregulatory genes may have facilitated adaptation to long lifespan

Behavioral genetics

Selection produces evolutionary change in behavior. Genes and loci that affect behavior. Genes influence behavior.

Behavioral stategies

1. fitness is independent of frequencies of other strategies (e.g. optimality)

2. fitness if dependent on the frequencies of other strategies in the population (e.g. ESS)

frequency-independent/optimality models

• optimal= performing the best possible stategy to maximize fitness

• optimal foraging — the energy gained from a food item is independent of what other are eating

Optimality models improved

• switch from energy to fitness as currency

• included learning about rules and environment as part of model

• include ‘state’ of animals in model to account for motivational and physiological conditions

• studying heritability of the strategies

Animal conflict: what is C

conventional tactics

Animal conflict: what is D

dangerous tactics

Animal conflict: what is R

retreat

Direct Fitness

the component of fitness gained through personal reproduction

indirect fitness

the component of fitness gained through aiding the survival and reproduction of non-descendant kin (i.e. siblings)

inclusive fitness

the fitness gain through both indirect and direct measures

altruism is likely to spread when (Hamiltons rule)

• benefits to recipient are great

• costs to actor are low

• participants are closely related

Br - C > 0

B, benefit to recipient

C, cost to actor

r, coefficient of relatedness