Study Flashcards for Human Evolution and Food Supply

These flashcards cover key concepts in human evolution and the impacts of food supply through various historical periods.

Neolithic Revolution

The transition from a nomadic hunter-gatherer lifestyle to settled farming communities, influenced by climate change, leading to population growth and the development of towns.

Extinction

A mass extinction is the loss of at least 75% of species within a short geological time frame, typically around 2 million years.

Invasive Species

Species that are non-native to an ecosystem and whose introduction can cause harm to the environment, economy, or human health.

Ecophysiology

The branch of biology that studies the interactions between physiological processes of organisms and their environments.

Primate Evolution

The evolutionary process through which modern primates, including humans, have adapted over millions of years, characterized by significant changes in diet and social behavior.

Cultural Practices in Food Production

Methods influenced by traditions, such as fire as a farming technique and varied cooking methods used by Aboriginal Australians to prepare and consume food.

Biodiversity Loss

The decline in the variety of life on Earth, largely due to human actions such as habitat destruction, climate change, and pollution.

Industrial Revolution

A period of major industrialization during the late 18th and early 19th centuries, marked by advancements in farming and production technologies.

Natural Selection

The process by which organisms better adapted to their environment tend to survive and produce more offspring, driving evolution.

Sensory Changes

Changes in perception and sensory responses that occur throughout the lifespan, influencing food choices and behaviors.

Evolution

All of the change that have transformed life over an immense time.

Adaptation

An inherited characteristic that improves an organism's ability to survive and reproduce in a particular environment.

Beagle

The ship that Charles Darwin sailed around the world with.

Descent with modification

Darwin's theory of species living on Earth today descended from earlier species.

Natural Selection

The process by which individuals with inherited characteristics well-suited to the environment leave more offspring on average than do other individuals.

Fossils

Preserved remains or markings left by organisms that lived in the past.

Fossil record

The collection of fossils recorded in rock layers over time.

Extinct

Species that no longer exist, help scientists reconstruct the past.

Homologous structures

Similar structures among related species.

Vestigial structures

Homologous structures that have a major function in one species but not in a related species.

Population

A group of individuals of the same species living in the same area at the same time.

Variation

Differences among members of the same species.

Artificial Selection

The selective breeding of plants and animals to produce offspring with traits that humans value.

Gene pool

Consists of all the alleles, or different forms of genes, in all the individuals in a population.

Microevolution

A generation-to-generation change in the frequencies of alleles within a population.

Hardy-Weinberg equilibrium

Populations that do not undergo change in their genes pools are not presently evolving.

Gene flow

The exchange of genes with another population.

Genetic drift

A change in a gene pool due to chance.

Fitness

The contribution that an individual makes to the gene pool of the next generation compared to the contribution of other individuals.

Antibiotics

Drugs that kill or slow the growth of bacteria.

Lamarck

Proposed that species evolved through inheritance of acquired characteristics. (use vs disuse)

Lyell

Geologist who proposed that gradual and observable geologic processes such as erosion could explain the physical features of today's Earth.

Malthus

Recognized that human populations can grow much faster than the rate at which supplies of food and other resources can be produced.

Buffon

Studying fossils led to suggest that Earth might be much older than a few thousand years.

Who/what influenced Darwin?

-Darwin was influenced by other early thinkers, including Lamarck, Lyell, and Malthus

-Darwin was also influenced by his knowledge of artificial selection.

-Wallace's paper on evolution confirmed Darwin's ideas.

Identify some key observations from Darwin's voyage that led to his theory.

Darwin found that species vary globally, locally, and over time.

Describe the two main points of Darwin's theory.

-Different, yet ecologically similar, animal species inhabited separated, but ecological similar, habitats around the globe.

-Modern organisms evolved over long periods of time through decent from common ancestors.

Describe information the fossil record contains about life on Earth.

The fossil record contains collections of fossils recorded in rock layers over time.

Examples of this are places such as Australia.

Tell how the geographic distribution of organisms relates to evolution.

The distribution of organisms relates to evolution because the best traits of organisms are selected.

Example: It's easy for an owl to spot a white mouse sitting on a dark rock. But it's very hard for an owl to spot a white mouse in the snow.

Explain how similarities in structure and development among different species are evidence for evolution.

Similar structures among related species provide clues about evolution.

Describe molecular evidence for evolution.

Molecular evidence can be used by comparing embryos of similar species and DNA sequences. The more similar the sequences, the more recently the species shared a common ancestor.

Summarize Darwin's theory of natural selection.

-More individuals are produced each generation that can survive.

-Phenotypic variation exists among individuals and the variation is heritable.

-Those individuals with heritable traits better suited to the environment will survive.

What are three direct pieces of evidence that support the theory of evolution by natural selection?

1.) Improvement of domesticated animals and plants by breeding individuals with desirable traits

2.) The fossil record that shows a clear relationship between living and extinct animals

3.) Homologous structures in different organisms that are dissimilar in form and function but that have underlying similar structures

Compare and contrast artificial selection with natural selection.

The only difference between natural selection and artificial selection is whether the difference in reproductive success is driven by naturally occurring processes, or whether the selection is imposed by humans. Explore Evolution obscures this in two ways.

Relate pesticide resistance in insects to natural selection.

Most survivors of the first pesticide treatments were insects with genes that somehow enabled them to resist the chemical attack. Their offspring inherited the genes for pesticide resistance - the population underwent evolutionary change that resulted in adaption to a change in the chemical environment - presence of the pesticides

Explain the significance of gene pools in understanding evolution.

Gene pools consist of all the alleles in all the individuals that make up a population. The population's gene pool is where genetic variation - the raw materials of evolution - is stored. The process of meiosis and fertilization shuffle alleles within the gene pool and deal them out to offspring in fresh combinations.

How does genetic drift contribute to changes in a gene pool?

Genetic drift is the change in the gene pool of a population due to chance. The smaller the population is, the more impact genetic drift has on that population.

How does gene flow contribute to changes in a gene pool?

Gene flow is the exchange of genes with another population. Gene flow occurs when fertile individuals or their gametes migrate between populations. Gene flow tends to reduce genetic differences between populations. If it is extensive enough, gene flow can eventually mix neighboring populations into a single population with a common gene pool.

How does mutation contribute to changes in a gene pool?

Mutation is a change in an organism's DNA. If the mutation is carried by a gamete, the mutation enters the population's gene pool. Mutation plays a key role in evolution as the original source of the genetic variation that is the raw material for natural selection.

How does natural selection contribute to changes in a gene pool?

Natural selection contributes to changes in a gene pool because it is the process by which individuals with inherited characteristics well suited to the environment leave more offspring on average than do other individuals

Explain what is meant by the term fitness.

Fitness is how an individual fits into an environment, meaning weather its features are beneficial or not for its surroundings. It is the contribution that an individual makes to the gene pool of the next generation compared to the contributions of other individuals.

Describe recent evidence for micro evolution on the Galapagos Islands.

For 30 years, the Grants and their students have been studying the finches on a isolated, uninhabited island. The islands small size and limited population of finches make it an excellent setting for studying natural selection. During wet years small seeds are so abundant that they eat only a few large seeds. But, during dry years large seeds make up a greater part of the bird's diet - and the birds with larger beaks have more success leading to more deaths. The surviving finches are more with those of larger beaks. The trend continues in the following generations. But during wet years, birds with small beaks eat the small seeds more efficiently than the larged beaked birds. The average beak size in the population is changed again.

In summary: Finches beak size plays as a role of recent micro evolution.

Explain how natural selection causes the sickle cell allele to persist in some gene pools.

Only homozygotes gave the disorder and heterozygotes are resistant to malaria. The people with the disorder commonly die as well as people who have malaria and are not resistant to it. Therefore, the people heterozygous for the sickle cell allele remain in the gene pool.

Explain how antibiotic resistance may evolve in bacteria.

While the drugs kill most of the bacteria, the resistant bacteria multiply. They quickly become widespread in the population.

Biological species concept

This concept defines a species as a population(s) whose members have the ability to breed with one another in nature and produce fertile offspring.

Speciation

The origin of a new species.

Macro-evolution

Major evolutionary changes.

-speciation

-extinction of species

-evolution of new features

Reproductive Isolation

The inability of different species to interbreed.

Barriers of Interbreeding:

-mating seasons

-behaviors

Geographic Isolation

Occurs when a population becomes separated from the rest of the species due to geographic change or movement to an isolated place. (event that leads to speciation)

Adaptive Radiation

When a population of a species evolve adaptations to a variety of different environments and form diverse new species.

Punctual Equilibrium

A model that describes long periods of little change are broken down by shorter times of more rapid change.

Embryology

The study of how organisms develop from fertilized eggs to fully formed organisms.

Relative Dating (fossils)

Finding the approximate age of a fossil due to its position in rock layers.

Absolute Dating (fossils)

Finding the exact age of a fossil by using radiometric dating.

Radiometric Dating

A method to determine the exact age of a fossil using the amount of radio active isotopes in the fossil.

Half-life

The time it takes for 50% of the original sample to decay.

Geologic Time Scale

A scale that organizes Earth's history into time periods.

What are the four times periods of Earth's history?

-Precambrian

-Paleozoic

-Mesozoic

-Cenozoic

Continental Drift

The movement of Earth's continents on large plates of crust.

Mass Extinction

An episode of great species loss.

Taxonomy

A branch of biology that involves the identification, naming, and classification of species.

What are the taxonomic ranks?

Domain

Kingdom

Phylum