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What is biodiversity?

The variety of life examined through genetic diversity, species diversity, and habitat diversity.

What does species diversity include?

Both the number of species (richness) and the relative proportions of each species (evenness) in a community.

What is genetic diversity?

The range of genetic material present in a particular gene pool or population of a species.

How does high genetic diversity benefit a species?

It makes a species more resistant to disturbances like disease.

What is habitat diversity?

The number of different habitats per unit area in an ecosystem or biome.

Give an example of an ecosystem with high species diversity.

Rainforests.

Why is high biodiversity advantageous?

It provides resilience and stability because many species can survive environmental changes.

What is Simpson’s Diversity Index?

A measure used to quantify biodiversity within a community.

What are biodiversity hotspots?

Regions with high levels of biodiversity that are under threat from human activities.

What percentage of habitat loss defines biodiversity hotspots?

Areas where 70% of the habitat has already been lost.

What is a criticism of biodiversity hotspots?

They often focus on vascular plants while ignoring animals.

What drives the evolution of diversity?

Environmental change that presents new challenges to species.

What is natural selection?

A process where individuals better adapted to their environment tend to survive and reproduce.

What is speciation?

The gradual change of a species over time leading to the formation of new species.

Name some physical barriers that cause speciation.

Mountain formation, changes in rivers, changes in sea level, climate change.

What is the background extinction rate?

The natural extinction rate of all species.

What have biologists proposed about the current extinction rate?

We are in the sixth mass extinction period due to human activities.

What human activities contribute to species extinction?

Habitat destruction, invasive species, pollution, overexploitation, hunting.

What effect does habitat complexity have on biodiversity?

The more complex the food web, the more resilient it is to the loss of a species.

What happens at the climax community stage of succession?

Species diversity may slightly fall as it reaches a stable point.

What are edge effects?

Fluctuations of light, temperature, and humidity at the edges of fragmented habitats.

How can pollution affect biodiversity?

Through local and environmental pollution, such as pesticides and eutrophication.

What does overexploitation refer to?

Unsustainable harvesting due to increased human population and pressure.

Why are island organisms more vulnerable?

Because they often have small populations and high rates of endemic species.

What is the IUCN Red List?

A list that monitors the conservation status of the world’s species.

What are reasons to conserve biodiversity?

Food sources, natural products, environmental services, gene pools, medicine.

What organizations are involved in biodiversity conservation?

Intergovernmental organizations (IGOs), governmental organizations (GOs), and non-governmental organizations (NGOs).

What is CITES?

A convention aimed at ensuring that international trade does not threaten wild species.

What is the goal of captive breeding?

To ensure species have proper care while preserving genetic diversity.

What are botanical gardens used for?

To grow plants for research, education, and conservation efforts.

What is a flagship species?

A charismatic species used to garner public support for conservation efforts.

What does the term 'keystone species' mean?

A species that plays a critical role in maintaining the structure of its ecosystem.

What are buffer zones in conservation?

Areas surrounding core reserves where limited human activity is allowed.

What does the term 'monoculture' refer to?

The agricultural practice of growing a single crop species over a wide area.

What is the significance of gene banks?

They preserve genetic material for future use in case species are lost.

What does genetic engineering in agriculture strive to achieve?

High-yielding crops or disease-resistant plants or animals.

What is the impact of modern agricultural practices on biodiversity?

They can lead to pollution and loss of biodiversity due to practices like monoculture and pesticide use.

Why are few populations of a species susceptible to extinction?

Fewer populations mean greater vulnerability to environmental changes.

What factors make a species prone to extinction?

Narrow geographical range, low population size, seasonal migration, specialized feeding.

What is inertia in ecosystem terms?

The ability of an ecosystem to resist change due to disturbances.

What is the significance of species richness?

It indicates the number of different species in a community.

What role does succession play in biodiversity?

It influences species diversity, with stages ranging from colonization to climax communities.

What are two factors that help maintain biodiversity?

Ecosystem complexity and limiting factors such as resource availability.

How does the introduction of alien species affect native species?

Non-native species can outcompete and disrupt local ecosystems.

What is adaptive significance in evolution?

Traits that provide an advantage to organisms in their environment.

What is habitat fragmentation?

The process of dividing larger habitats into smaller, isolated fragments.

What are environmental services provided by biodiversity?

Processes like pollination, nutrient cycling, and soil aeration.

Why is it important to preserve old varieties of crops?

They may offer genetic resources for developing pest- and disease-resistant varieties.