Exam 4 Study Guide: Ecology, Community Interactions, and Conservation

This set of flashcards covers key concepts from Exam 4 material, including ecological foundations, aquatic zonation, population models, species interactions, and conservation science.

What is the scientific definition of Ecology?

The scientific study of interactions between organisms and their environment.

How many branches of ecology are mentioned in the notes?

$$6$$

What are the six branches of ecology summarized in the text?

Organismal, Population, Community, Ecosystem, Landscape, and Global (Biosphere).

What is the term for the specific environments where organisms live?

Habitats

Which geographical area is characterized by rising moisture-rich air due to high intensity sunlight?

The equator

At which specific latitudes does dry air descend within the global circulation model?

$30^{\circ}$ latitudes

In aquatic zonation, what distinguishes the photic zone from the aphotic zone?

The photic zone has light, while the aphotic zone has little or no light.

Which colors of light are identified as penetrating the deepest in aquatic environments?

Blue and green light

What is the thermocline?

A narrow layer of abrupt temperature change separating warm upper layers from cold deeper waters.

Which lake zone is described as being shallow with rooted plants?

Littoral

What is the name of the open water zone in a lake?

Limnetic

What is the shape of the growth curve for exponential population growth?

$J$-curve

Which growth curve shape represents logistic population growth?

$S$-curve

In population growth models, what does the variable $K$ represent?

Carrying Capacity

How is resource partitioning defined in community ecology?

Differentiation of niches that enables similar species to coexist in a community.

What are three examples of predator adaptations listed in the notes?

Senses, claws, and venom.

What is cryptic coloration?

Camouflage used as a prey defense.

Which prey defense involves warning colors, such as those found on a poison dart frog?

Aposematic Coloration

What is the definition of Batesian Mimicry?

A harmless species mimicking a harmful one.

How is the symbiotic relationship of mutualism represented symbolically?

$$(+/+)$$

How is the symbiotic relationship of parasitism represented symbolically?

$$(+/-)$$

How is the symbiotic relationship of commensalism represented symbolically?

$$(+/0)$$

What is the structural difference between food chains and food webs?

Chains are linear, while webs are complex branching networks.

How does the transcript define a Keystone species?

A species with a pivotal ecological role.

What are Engineers in an ecological context, and what is a provided example?

Physical modifiers of the environment; beavers are an example.

What are the three identified levels of biodiversity?

Genetic diversity, Species diversity, and Ecosystem diversity.

What is identified as the single greatest threat to biodiversity?

Habitat loss

According to the transcript, what percentage of energy is transferred between trophic levels?

$$10\%$$

What is biomagnification?

The process where toxins become more concentrated in successive trophic levels.

Which two greenhouse gases are mentioned as trapping heat in the atmosphere?

$CO_2$ and $CH_4$

What is meant by 'species diversity'?

The variety of different species within a specific habitat or ecosystem.

What does 'genetic diversity' refer to?

The total number of genetic characteristics in the genetic makeup of a species.

What is 'ecosystem diversity'?

The variety of ecosystems within a given region.

What role do decomposers play in ecosystems?

They break down dead organic material, recycling nutrients back into the ecosystem.

What are two major types of ecological succession?

Primary succession and secondary succession.

What is the difference between primary succession and secondary succession?

Primary succession occurs on lifeless surfaces, while secondary succession occurs in areas that previously supported life.

What is an example of a density-dependent factor affecting population growth?

Competition for resources.

What is a density-independent factor affecting population growth?

Natural disasters, such as hurricanes.

How do invasive species impact ecosystems?

They can outcompete native species for resources, disrupting the ecological balance.

What is the concept of an ecological footprint?

A measure of human demand on Earth's ecosystems, representing the amount of natural capital used.

What is a keystone species?

A species that has a disproportionately large effect on its environment relative to its abundance.

What are ecological niches?

The role and position a species has in its environment, including all interactions with biotic and abiotic factors.

What is habitat fragmentation?

The process where a large expanse of habitat is divided into smaller, isolated sections, typically due to human activities.

What are invasive species?

Non-native species that spread widely and cause harm to the environment, economy, or human health.

What is demographic transition?

The transition from high birth and death rates to lower birth and death rates as a country develops from pre-industrial to industrialized economic systems.

What is biodiversity loss?

The reduction in the variety of life, including species extinction and habitat destruction, often due to human activities.

What is ecological resilience?

The ability of an ecosystem to withstand disturbances and recover from them.

What are the primary causes of habitat destruction?

Agricultural expansion, urbanization, pollution, and logging.

What is the role of top predators in ecosystems?

Top predators help maintain the population balance of prey species, influencing the structure of the ecosystem.

What is the importance of pollinators in ecosystems?

Pollinators are crucial for the reproduction of many plants, which are foundational to ecosystem stability and food webs.

What is ecological succession?

The process by which ecosystems change and develop over time, involving a series of species replacements.

What is primary succession?

The establishment of a biological community in an area that was previously devoid of life, such as after a volcanic eruption.

What is secondary succession?

The re-colonization of an area after a disturbance that leaves the soil intact, such as after a forest fire.

What is a pioneer species?

The first species to colonize previously disturbed or barren environments, initiating the process of ecological succession.

What is an ecological niche?

The role and space an organism fills in an ecosystem, encompassing its habitat, resource use, and relationships with other species.

What are trophic levels?

The hierarchical levels in an ecosystem, comprising producers, primary consumers, secondary consumers, and tertiary consumers.

What is the concept of carrying capacity?

The maximum population size of a species that an environment can sustain indefinitely without degrading the habitat.

What is biomagnification?

The increasing concentration of toxins in organisms at each successive trophic level within an ecosystem.

What is the edge effect?

The different conditions that occur along the boundaries of ecosystems, often supporting diverse species and interactions.

What is a community in ecology?

A group of interacting species sharing a common habitat, which can include organisms from different taxa.