Biodiversity and Evolution: Key Concepts and Ecosystem Roles

What is biodiversity?

The variety of life in the world or in a particular habitat or ecosystem.

What are the four types of biodiversity?

Species diversity, ecosystem diversity, functional diversity, and genetic diversity.

What is species diversity?

The number of different species and their abundance in a community.

What is ecosystem diversity?

The variety of biomes or ecosystems in an area.

What is functional diversity?

The variety of biological and chemical processes that take place in an ecosystem.

What is genetic diversity?

The variety of genetic material (genes) in a species or population.

What are some negative impacts of insects?

Competing for food, spreading diseases (like malaria), biting or stinging, and invading homes.

What are some positive impacts of insects?

Pollination, controlling pest populations, and renewing topsoil.

What is biological evolution?

The process where life changes over time due to genetic changes within a population.

What is natural selection?

The process where certain individuals with advantageous genetic traits survive and reproduce more successfully.

Who are the key figures associated with the theory of evolution?

Charles Darwin and Alfred Russel Wallace.

What does the Tree of Life represent?

The view that life develops and diversifies similarly to how a tree branches.

How do populations evolve?

Populations evolve by becoming genetically different, not individuals.

What is genetic variation?

The first step in biological evolution, occurring through random mutations in reproductive cells.

What is adaptation in the context of evolution?

An inherited trait that increases an organism's chance of survival and reproduction in a specific environment.

What are structural adaptations?

Physical traits or chemical processes that enhance survival, like thorns or toxins.

What is mimicry?

The ability of one organism to imitate the appearance or behavior of another.

What is camouflage?

An organism's ability to blend in with its surroundings.

What is coloration in terms of adaptation?

The use of bright colors to warn other species of danger, attract prey, or distract prey.

What are three common myths about evolution through natural selection?

1. 'Survival of the fittest' is not 'survival of the strongest.' 2. Organisms do not develop traits out of need or want. 3. There is no grand plan of nature for perfect adaptation.

How do geologic processes affect natural selection?

Tectonic plates influence evolution and species distribution; earthquakes and volcanic eruptions can isolate or create habitats.

How does climate change affect natural selection?

Ice ages and warming temperatures alter where plants and animals can live, leading to changes in biomes.

What are the effects of asteroid collisions on evolution?

They can lead to the emergence of new species, extinction events, and shifts in ecosystems.

What are the conditions necessary for life to thrive on Earth?

A certain temperature range, dependence on water, axial rotation, revolution around the sun, and sufficient gravitational mass.

What is geographic isolation?

Geographic isolation occurs when different groups of the same population become physically separated for a length of time, leading to allopatric speciation.

What is allopatric speciation?

Allopatric speciation is the evolution of species due to geographic isolation.

What is reproductive isolation?

Reproductive isolation occurs when mutations make genes so different that members can no longer reproduce viable, fertile offspring.

What are the types of reproductive isolation?

Types include temporal isolation, behavioral isolation, mechanical isolation, and gametic isolation.

What is temporal isolation?

Temporal isolation is a form of reproductive isolation where species breed at different times.

What is behavioral isolation?

Behavioral isolation occurs when species have different mating rituals, dances, songs, or pheromone production.

What is mechanical isolation?

Mechanical isolation happens when the reproductive organs of species are no longer compatible.

What is gametic isolation?

Gametic isolation occurs when gametes are unable to fertilize each other, leading to sterility.

What is extinction?

Extinction is the end of an organism or species, which can affect one species or many species at a time.

What is background extinction?

Background extinction is the average rate of extinction occurring before humans arrived, estimated at about 1 species every 500-1000 years.

What is mass extinction?

Mass extinction refers to rapid, catastrophic events that can wipe out 40-90% of species globally.

What is species richness?

Species richness is the number of different species in a given area.

What is species evenness?

Species evenness is the abundance of individuals within each species in a community.

What is the species equilibrium model?

The species equilibrium model, or theory of island biogeography, states that the rate of new species immigrating should balance with the rate of species extinction.

What is an ecological niche?

An ecological niche is the pattern of living and role of a species within its ecosystem.

What are generalist species?

Generalist species have a broad niche and can thrive in a variety of environments.

What are specialist species?

Specialist species have a narrow niche and are adapted to specific environmental conditions.

What are native species?

Native species are those that naturally occur in a specific area.

What are nonnative species?

Nonnative species, also known as invasive, alien, or exotic species, may spread rapidly and negatively impact ecosystems.

What are indicator species?

Indicator species are organisms that can monitor environmental quality and indicate changes in the ecosystem.

What are some examples of indicator species?

Examples include frogs, trout, birds, and butterflies.

What are keystone species?

Keystone species are those that have a disproportionately large impact on their ecosystem, such as pollinators and top predators.

What are foundation species?

Foundation species are those that build or enhance their habitats, benefiting other species, such as elephants and beavers.

Why are elephants considered keystone species?

Elephants influence their ecosystem by feeding on smaller trees, maintaining the savanna ecosystem.

Are humans considered a keystone species?

Humans are debated as keystone species; our negative impact is often larger and more long-term than our positive influence.

What are amphibians and why are they significant?

Amphibians are a class of animals that includes frogs, toads, and salamanders. They are significant as they are sensitive biological indicators of environmental changes.

What percentage of known amphibian species face extinction according to the IUCN?

About 33% of known amphibian species face extinction.

How much faster are frogs going extinct compared to historical rates?

Frogs are going extinct 10,000 times faster than their historical rates.

What are three reasons why we should care about amphibian extinctions?

1. They are sensitive indicators of environmental changes. 2. They play important roles in biological communities. 3. They contribute to human health through pharmaceutical compounds.

What human activities threaten amphibian populations?

Human activities such as the use of pesticides and other chemicals pollute their land and water habitats.

What role do adult amphibians play in biological communities?

Adult amphibians eat more insects than many species of birds, helping control insect populations.

What potential medical benefits do amphibians provide?

Compounds found in amphibian skin secretions are used in painkillers, antibiotics, and treatments for burns and heart disease.

What is the difference between eukaryotic and prokaryotic organisms?

Eukaryotic organisms have cells with a distinct nucleus and membrane-bound structures, while prokaryotic organisms, like bacteria, do not.

Name one example of an organism from the kingdom of protists.

Examples include algae and protozoans.

What are the two types of bacteria recognized in biological classification?

Eubacteria and archaebacteria.

What is the largest category in taxonomic classification?

The kingdom is the largest category in taxonomic classification.

What distinguishes a species in sexually reproducing organisms?

Individuals must be able to mate with similar individuals and produce fertile offspring.

How many species have biologists identified so far?

Biologists have identified about 2 million species.

What are the two main groups of animals based on the presence of backbones?

Invertebrates (no backbones) and vertebrates (with backbones).

What is the estimated range of total species on Earth?

Estimates range from 7 million to 100 million species.

What are the four kingdoms of eukaryotic organisms?

Protists, plants, fungi, and animals.

What are annual and perennial plants?

Annuals live for one growing season, while perennials can live for two or more seasons.

What is the role of amphibians in ecosystems?

They help control insect populations and serve as prey for various animals.

What is the significance of amphibians as biological indicators?

Their sensitivity to environmental changes indicates the health of ecosystems.

What is the taxonomic classification hierarchy from kingdom to species?

Kingdom > Phylum > Class > Order > Family > Genus > Species.

What is the genus and species name for humans?

Homo sapiens.

What is the impact of habitat loss on amphibians?

Habitat loss contributes to their declining populations and increased extinction rates.

What are some factors affecting amphibian life cycles?

Pollution, habitat loss, climate change, and UV radiation.

How do frog eggs differ from other eggs in terms of protection?

Frog eggs lack shells, making them vulnerable to water pollutants.

What are some examples of vertebrates?

Amphibians, fishes, reptiles, birds, and mammals.

What is the role of insects in ecosystems that humans depend on?

Insects provide essential ecosystem services, such as pollination and pest control.

What is the significance of biodiversity?

Biodiversity is crucial for ecosystem stability, resilience, and providing resources for human health.

What are the four components of biodiversity?

Species diversity, genetic diversity, ecosystem diversity, and functional diversity.

Define species diversity.

The number and abundance of different kinds of species living in an ecosystem.

How does species richness affect ecosystem stability?

Species-rich ecosystems tend to be more stable than those with low species richness.

Why is genetic diversity important?

It allows species to adapt to environmental changes and increases their chances of survival.

What are biomes?

Large regions characterized by distinct climates and certain prominent species.

What role do insects play in ecosystems?

Insects provide vital services like pollination and pest control, and they contribute to food supplies in some regions.

How do human activities threaten insect populations?

Human activities such as habitat destruction and pesticide use threaten the survival of many insect species.

What is the significance of pollination?

Pollination is essential for the reproduction of flowering plants, which are crucial for many ecosystems.

What is the impact of low species evenness?

Low species evenness indicates that one or more species dominate, which can reduce ecosystem resilience.

What are edge effects?

Environmental conditions and species variations that occur at the boundaries between different habitats.

How do tropical rainforests compare to tree farms in terms of biodiversity?

Tropical rainforests have high species richness and evenness, while tree farms typically have low species richness and evenness.

What is the estimated number of species on Earth?

Scientists estimate there are between 7 million to 100 million species on Earth.

What is the role of decomposers in ecosystems?

Decomposers break down organic matter, recycling nutrients and supporting ecosystem health.

What is the importance of the phylum Chordata?

Chordata includes animals with a notochord, nerve cord, and pharynx, which are key features for vertebrates.

What distinguishes the class Mammalia?

Mammals have hair or fur, warm blood, and produce milk to nourish their young.

What are the characteristics of the family Hominidae?

Hominidae includes upright animals with two-legged locomotion and binocular vision.

What defines the genus Homo?

The genus Homo includes upright animals with large brains and the capacity for language.

What is the significance of Homo sapiens sapiens?

Homo sapiens sapiens represents modern humans capable of sophisticated cultural evolution.

What is the ecological role of the praying mantis?

The praying mantis helps control pest populations by preying on other insects.

How does biodiversity contribute to natural capital?

Biodiversity is a key component of natural capital, providing essential ecosystem services and resources.

What is the difference between a forest edge and a forest interior?

A forest edge is more open, bright, and windy, with greater variations in temperature and humidity than a forest interior.

What impact do humans have on natural ecosystems?

Humans have fragmented many forests and grasslands into isolated patches, reducing core habitat and increasing edge habitat that supports fewer species.

What is an ecotone?

An ecotone is a transitional zone where one ecosystem merges with another, containing a mixture of species from both ecosystems and some migrant species.

What is functional diversity in ecosystems?

Functional diversity refers to the variety of processes, such as energy flow and matter cycling, that occur within ecosystems as species interact.