Evolution and the Biosphere

Flashcards covering key concepts from lecture notes on evolution, natural selection, and the biosphere.

What is the dictionary definition of evolution, and what are some issues with it?

Process of continuous change from a lower, simpler, or worse state to a higher, more complex, or better state; this definition has problems related to pace and potential harm of changes.

How do genetic mutations and environmental factors affect viruses?

Genetic mutations can lead to rapid changes in the virulence of the flu; an unchanging environment may not force change.

What evidence exists that supports the idea that evolution does not always result in increasing complexity?

Fossils that document hindlimb loss as ancestors of whales transition from land to sea.

What is hindlimb loss and when does it occur during embryonic development?

A process where hindlimbs begin to form but do not fully develop due to changes in gene expression; this process occurs during weeks 4-9 of embryonic development.

How can viral reassortment lead to evolutionary success in viruses?

Viral reassortment allows flu strains to infect new hosts, making even a "lowly" virus an evolutionary success because it survives and reproduces.

How does natural selection lead to evolution in viral strains?

Beneficial mutations increase in frequency through natural selection; leads to a change in populations' genetics where the highest reproducer dominates.

What is the biological definition of evolution?

Change from generation to generation in populations of organisms differing genetically in one or more traits.

What is the dictionary definition of science?

Knowledge obtained through study or practice; an attempt to discover nature and then predict the future.

What are the steps of the scientific method?

Observation, question, hypothesis formulation, experiment design, data collection, results analysis, conclusion drawing, publication by peer review, and repeated support leading to a theory.

What is an important distinction to make when analyzing scientific data?

Correlation does not equal causation.

What is an argument against evolution as a science?

Events unique and not replicable.

What is an argument supporting evolution as a science?

Rules are open to disproof.

What factors contribute to the differential heating of the planet?

Curved surface, tilted axis, rotation, and altitude.

How do convection cells affect climate?

Hot air rises, cools, and precipitates, then sinks, leading to wet equators and dry subtropics.

What is the Coriolis effect and how does it influence wind patterns?

Equator moves faster than poles, causing deflection of winds; in the Northern Hemisphere, winds deflect right.

What are the primary climatic controls?

Latitude, topography, continental vs. maritime influences, and prevailing pressure systems.

What is a microclimate and why is it important?

A small-scale climate that is most important to organisms, influenced by factors like shade and proximity to water.

What are biomes and what determines them?

Largest ecological unit, characterized by vegetation and soil; terrestrial biomes include tropical rain forest, savanna, desert, deciduous forest, and grasslands.

What are the characteristics of a tropical rain forest?

Rainy, stratified canopy, little temperature variation, poor soils due to decomposition and leaching.

What are the characteristics of a tropical savanna?

Open grass with scattered trees, wet/dry seasons with fire, wandering grazers, human origins.

What are the characteristics of a tropical desert?

Evaporation exceeds rainfall, bands ringed globe at 30o N&S, drought & flood, wide daily temp. variation, little vegetation (cacti & succulents), low organic soils (islands), animals are water conservers.

What are the characteristics of a temperate deciduous forest?

Deciduous trees & some conifers, moderate temperature variation, moist, richer soils.

What are the characteristics of a temperate grassland (steppe)?

Hot & cold, grasses & grazers, drought, fire, flat terrain, good agricultural land (Great Plains).

What are the characteristics of a temperate desert?

Evaporation > rainfall, cooler at night, & moister more vegetation & flowers during moist season than tropical desert.

What are the characteristics of a Northern coniferous (boreal) forest (taiga)?

Evergreen forest, some birches/aspens, cold winters, bogs (permafrost), large mammals.

What are the characteristics of a tundra?

Polar grassland, permafrost, low vegetation (or above treeline), very cold, little solar E.

What are the characteristics of a cool/cold desert?

High altitude or latitude, cold at night (huge temp. extremes), evaporation > precipitation, (warm during day = scrub/sagebrush).

What effects do altitude have?

Mimic the effects of latitude.

What key factors determine biomes?

Temperature and precipitation.

What human activities stress the biosphere?

Pollution, acid rain, deforestation, land use, global warming.

What is Plato and Aristotle's idealism?

Everything, including animals, represented by an ideal (archetype); also includes the Ladder of Nature or Great Chain of Being.

What did Linnaeus's binomial nomenclature contribute to?

Nested hierarchical structure.

What is spontaneous generation?

Living organisms from non-living material.

What were Darwin's observations that conflicted with the 4,000 B.C. origin of Earth?

Fossil evidence, geographic distributions, island organisms, selective breeding.

What did Nicolas Steno contribute?

Change in fossils reconstructs the past.

What did Jean-Baptiste Lamarck contribute?

Evolution through acquired traits.

What did Georges Buffon contribute?

Earth followed laws of physics & chemistry, old Earth.

What is Lamarck's theory of evolution?

The neck stretching example: acquired traits are not inherited!

What did Malthus contribute?

Human population will increase exponentially, faster than food supply, and is limited by its subsistence.

What did Darwin and Alfred Russel Wallace recognize?

Real populations don’t expand at an exponential rate, individuals vary, some heritable traits assist survival and reproduction adaptations survival of the fittest and differential reproduction.

What did Darwin and Alfred Russel Wallace contribute about the evolution by natural selection

Interaction between individuals & environment (living (biotic) & non-living (abiotic)) determines the number of descendants, better adapted locally more reproduction, population (not individual) is more closely matched to its environment and selection acts not just to preserve, but to create new types.

How natural selection lead to antibiotic resistance selection for MRSA

Any bacteria that are randomly resistant to the antibiotic (selection pressure) can better survive and reproduce; frequency (proportion) of resistant bacteria increases in the surviving population.

what does improvement mean

Match.

what is peppered moth?

Light and dark versions of the species.

When did the proportion of the dark vs. light phenotypes change rapidly when the color of the tree bark changed

When the color of the tree bark changed with pollution and when cleaned up

According to Charles Darwin, what does Natural Selection do

Individuals having any advantage, however slight, over others, would have the best chance of surviving and of procreating their kind.

Why no perfection in Natural Selection?

Changing environment, selection only acts on existing traits, speed of change depends on magnitude of selection pressure.