Ecology: Herbivory, Predation, and Community Structure

Flashcards covering core vocabulary terms and ecological concepts from the lecture, including herbivore feeding types, predator-prey dynamics, defenses, group living, and community structuring.

Grazers

Herbivores that specialize in feeding on low-lying vegetation such as grasses.

Browsers

Herbivores that specialize in eating tree leaves, branches, twigs, and vegetation positioned higher off the ground.

Granivores

Herbivores or seed predators that selectively feed on the seeds of plants.

Monophagous

Describing herbivores or predators that specialize strictly on a single host or prey species.

Oligophagous

Describing consumers that feed on a narrow, restricted range of species, typically limited to a single taxonomic family.

Golden Apple Snail

An invasive generalist herbivore that can consume and remove all large plants, algae, and detritus from wetland ecosystems.

Huffaker's 1958 Experiments

Laboratory studies using herbivorous and predatory mites on oranges and rubber balls showing that simple environments lead to mutual extinction, whereas habitat complexity allows coexistence and population cycling.

Spatial Refuges

Complex physical structures or environmental heterogeneity that provide hiding places where prey can evade predators and avoid local extinction.

Metapopulations

Spatially separated subpopulations of a species that experience localized extinctions and recolonizations across patches over time.

Aposematic Coloration

Bright, conspicuous warning coloration that advertises chemical toxicity, unpalatability, or venom to potential predators.

Crypsis

A form of camouflage or mimicry where an organism blends into its environment using visual patterns, physical shapes, or chemical pheromones to evade detection.

Chemical Sequestration

The physiological accumulation and storage of dietary toxic compounds by an organism within its own body tissues for anti-predator defense.

Dilution Effect

A defensive benefit of group living where the statistical probability of any single individual being targeted and killed by a predator decreases as group size increases.

Optimal Group Size

The group size at which the net fitness benefits of group living maximally outweigh the energetic and competitive costs.

Plant Compensation

An adaptive response to herbivory in which tissue damage stimulates the plant to produce increased aboveground biomass, vegetative growth, or reproductive output.

Secondary Metabolites

Chemical compounds synthesized by plants outside primary pathways like photosynthesis and cellular respiration, functioning as toxins, deterrents, or signals that attract natural enemies of herbivores.

Cardiac Glycosides

Toxic secondary metabolites produced by plants such as milkweed that interfere with vertebrate heart function and are sequestered by monarch butterflies for chemical defense.

Tetrodotoxin

A lethal neurotoxin produced by animals such as certain newts, against which specific predators like garter snakes have evolved enzymatic or physiological resistance.

Yellowstone Wolf Reintroduction

A management action demonstrating top-down predator control: reintroducing gray wolves reduced elk overbrowsing, restored woody riparian plants like willows and aspens, and facilitated the return of beavers.

Arctic Fox Introduction (Aleutian Islands)

An ecological event where introduced foxes devastated ground-nesting seabird populations, drastically reducing guano nutrient deposits (nitrogen and phosphorus) and transforming lush maritime grasslands into tundra dominated by mosses and lichens.