Biology Evolution Concepts

Typological Thinking

• Early species classification grouped species with minimal variance.

Scala Naturae

• Aristotle's ranking system categorized species based on size and perceived complexity.

Uniformitarianism

• Earth's geological processes are consistent and ongoing.

Fossils

• Fossil discoveries revealed extinct organisms, challenging established views of Earth's history.

Jean-Baptiste Lamarck

• Proposed evolutionary ideas but incorrectly suggested traits acquired during an organism's lifetime could be passed to offspring.
• Also proposed spontaneous generation.

Charles Lyell

• Lyell's uniformitarianism influenced Darwin's ideas on gradual change in species.

Darwin's Voyage

• Darwin observed fossils, environmental changes due to earthquakes, and variations in tortoises across different islands.

Origin of Species

• Darwin published "On the Origin of Species," detailing the theory of natural selection.
• Darwin's observations from his voyage led to the development of natural selection.

Wallace

• Wallace independently reached similar conclusions about natural selection as Darwin.
• The Wallace Line showcases different species distributions in Asia and Australia.

Comte de Buffon

• Advocated for empiricism, the use of evidence-based scientific claims.

Adaptation

• A heritable trait that increases survival and reproduction in a specific environment.

Fitness

• An individual's ability to produce viable offspring relative to others of the same species.

Variation

• Variation within a population is crucial for natural selection, as heritable variation allows populations to evolve.

Conditions for Evolution by Natural Selection

• Variation, Heritability, Differential survival and reproduction, population growth

Wallace's Line

• The Wallace Line marks a boundary in the distribution of species between Asia and Australia.

Descriptive Statistics in Life Science

• Quantitative tools for measuring differences and variations in populations.

Directional Selection

• Selection that shifts the population mean in one direction.

Stabilizing Selection

• Selection maintaining the population mean and reducing variation.

Disruptive Selection

• Selection favoring both extremes of a trait distribution

Example of Directional Selection

• Antibiotic resistance evolution.

Example of Stabilizing Selection

• Galapagos finches with intermediate beak sizes favored during drought.

Example of Disruptive Selection

• Pocket mice with light or dark fur favored over intermediate colors for camouflage.

Convergent Evolution

• The independent evolution of similar traits in unrelated species.

Genetic Drift

• Random changes in allele frequencies due to chance events, leading to loss or fixation of alleles

Founder Effect

• A small population establishes a new population and carries different allele frequencies.

Population Bottlenecks

• Sudden reduction in population size that alters allele frequencies independent of adaptation.

Genetic Drift is Most Potent When

• Populations are small, and allele frequencies are limited.

Gene Flow

• Movement of alleles between populations through migration and breeding.

Importance of Gene Flow

• Increases genetic variation within populations but reduces it between populations.

Mutation

• A random process that introduces new genetic variation.

Inbreeding Depression

• Decrease in fitness due to increased homozygosity and reduced heterozygosity.

Hardy-Weinberg Equilibrium

• Conditions where allele and genotype frequencies remain constant.

Hardy-Weinberg Equations

• p+q=1 and p^2+2pq+q^2=1

Conditions for Hardy-Weinberg Equilibrium

• Random mating, no mutations, no genetic drift, no gene flow, and no natural selection

Random Mating

• Mate selection without preference or bias.

Sexual Selection

• Traits that increase mating success but may not increase survival.

Sexual Dimorphism

• Differences in traits between males and females within a species.

Secondary Sexual Traits

• Traits specific to one sex but not directly related to reproduction.

Parental Investment

• Resource allocation by a parent to increase offspring survival

Female investment

• Greater energy invested in offspring because females produce eggs/ova.

Male investment

• Competition, displays, etc

Variation in Reproductive Success

• Differences in successful mating by males and females.

Variance

• Variance is a key component in sexual selection.

Direct Benefits of Mate Choice

• Food, protection, etc.

Indirect Benefits of Mate Choice

• Attractiveness, good genes of the mate.

Good Genes Hypothesis

• Preference for extreme traits as indicators of good health.

Runaway Selection Hypothesis

• Extreme sexual traits become prevalent due to positive feedback.

Species

• Evolutionary independent population(s).

Biological Species Concept

• Reproductive isolation as the defining feature of species.

Morphospecies Concept

• Morphological similarity as the indicator of species.

Phylogenetic Species Concept

• Species defined by cladistic monophyly (monophyletic groups).

Cryptic Species

• Two species that look alike but are reproductively isolated .

Prezygotic Isolation

• Mechanisms preventing mating between species.

Temporal Isolation

• Breeding occurring at different times.

Habitat Isolation

• Species occupying different habitats.

Behavioral Isolation

• Species with different mating rituals.

Gametic Isolation

• Incompatible egg and sperm.

Mechanistic Isolation

• Physical incompatibility preventing mating.

Postzygotic Isolation

• Reduced fitness in offspring of interspecies mating.

Hybrid Inviability

• Hybrid offspring fail to develop.

Hybrid Sterility

• Hybrid offspring cannot reproduce.

Outgroup

• Ancestral group on a phylogeny.

Node

• Points where branches split on a phylogenetic tree.

Polytomy

• Branch point with more than two lineages.

Synapomorphy

• Shared derived trait.

Monophyletic Group

• Group including ancestor and all its descendants.

Paraphyletic Group

• A group that includes the common ancestor but not all descendants.

Polyphyletic Group

• A group that does not include the common ancestor .

Homology

• Similarity due to common ancestry.

Homoplasy

• Similarity due to convergent evolution or other reasons.

Speciation

• The formation of new species.

Allopatric Speciation

• Speciation due to geographic isolation (dispersal or vicariance).

Sympatric Speciation

• Speciation within the same geographic area.

Ring Species

• Species interbreeding along a geographic ring.

Hybrid Zones

• Region where interbreeding occurs and fitness is reduced.

Adaptive Radiation

• Rapid speciation from a common ancestor.

Parameters for Adaptive Radiation

• Rapid speciation, trait-environment correlations, trait utility, and common ancestry.

Ecological Theory of Adaptive Radiation

• Phenotypic divergence, competition, ecological separation and new species.

Mass Extinction

• Widespread extinction of species.

Background Extinction

• Normal extinction rate.

Cambrian Explosion

• Rapid diversification of life 542 million years ago.

Permian Mass Extinction

• Catastrophic extinction event 250-248 million years ago.

K–Pg extinction

• Mass extinction 65 million years ago, causing dinosaur extinction.

6th Mass Extinction

• Current period of accelerated extinction.

Animal Migrations

• Periodic movement between locations.

Baby Turtle Senses

• Vision, wave orientation, and magnetic fields help them navigate.

Adult Turtle Navigation

• Adult turtles use magnetic fields for true navigation, understanding their location in relation to their goal.

Polygyny

• One male mates with multiple females, often involving habitat or group defense.

Polyandry

• One female mates with multiple males, often involving resources or defenses.

Promiscuity

• No prolonged interactions between males and females

Monogamy

• Long-term pairing between one male and one female.

Defendability

• The ability to protect mates and resources for reproduction .

Population

• Group of interbreeding or potentially interbreeding individuals.

Major Characteristics of Populations

• Geographic range, size, and spatial distribution.

Dispersion (Spatial Distribution)

• Clumped, uniform, or random.

Population Demography

• Factors influencing population size and structure.

Factors influencing Population Size

• Emigration, immigration, births, deaths.

Factors influencing Population Structure

• Age distribution, survival rates, offspring production by different age groups.

Age Pyramids

• Visual representation of age distribution in a population, useful for assessing stage of development.

Life Tables

• Summarization of survival and reproduction rates in a population.

This quiz explores fundamental concepts in evolutionary biology, including typological thinking, Scala Naturae, and the contributions of key figures such as Lamarck and Darwin. Test your knowledge of species classification, fossil discoveries, and the principles behind natural selection and uniformitarianism.