WEEK NINE

Comprehensive vocabulary flashcards covering ecological niches, life history strategies, predator-prey dynamics, and parasitism/One Health concepts from Lectures 25, 26, and 27.

Ecological Niche

The set of conditions, resources, and ecological roles/relationships a species requires to survive and persist, rather than simply a physical space.

Habitat

The physical space or geographic location where an organism lives.

Hutchinsonian Niche

An $n$-dimensional hypervolume or hyperspace encompassing all the abiotic and biotic environmental conditions and resources that permit a species to survive and maintain viable populations.

Fundamental Niche

The complete multi-dimensional space of environmental conditions and resources where a species could theoretically survive in the absence of limiting biotic interactions, determined solely by its physiological tolerances.

Realised Niche

The actual portion of the fundamental niche that a species occupies, which is always smaller than the fundamental niche due to competition, dispersal limitation, disturbances, and stochastic events.

Biogeography

The study of the geographic distributions of species across landscapes and time, along with the ecological and evolutionary factors that drive these patterns.

Life History

The overall pattern of growth, survival, and reproduction across an organism's lifespan.

Trade-Off

An inescapable compromise in allocating finite energy and resources between competing biological functions, such as growth, maintenance, survival, and reproduction.

$r$-selected Strategy

A life history strategy maximizing the intrinsic rate of population growth ($r$), characterized by producing many small offspring, early reproductive maturity, rapid growth, low competitive ability, short lifespan, and boom-and-bust population dynamics.

$K$-selected Strategy

A life history strategy focusing on long-term survival near environmental carrying capacity ($K$), characterized by producing few large offspring, high parental investment, late maturity, slow growth, high competitive ability, and long lifespan.

Survivorship Curve

A standardized plot on a logarithmic scale showing the number or proportion of individuals from a cohort surviving at each age interval over their lifespan.

Type I Survivorship Curve

A survivorship pattern characterized by high survival throughout early and middle life, with low juvenile mortality and the majority of deaths occurring late in life (typical of $K$-selected species).

Type II Survivorship Curve

A survivorship pattern with a roughly constant rate of mortality per unit time across all age classes, represented by a straight declining line on a logarithmic scale.

Type III Survivorship Curve

A survivorship pattern with extremely high juvenile mortality and relatively low mortality for the few individuals that reach adult life (typical of $r$-selected species).

Semelparity

A reproductive strategy in which an organism devotes all accumulated reproductive resources to a single, intensive breeding event in its lifetime, typically followed directly by death.

Iteroparity

A reproductive strategy in which an organism engages in repeated, distinct reproductive episodes spread across multiple breeding seasons or intervals throughout its life.

Annual

An organism whose life cycle, from germination or birth to reproduction and death, is completed within a single calendar year or season.

Perennial

An organism whose individual lifespan and generation span multiple years.

Predation

A species interaction in which an individual of one species consumes all or part of an individual of another species, encompassing true carnivory, herbivory, and parasitism.

Specialist Predator

A predator possessing a narrow diet focused on specific prey types, evolving specialized adaptations for high capture and extraction efficiency at the risk of vulnerability if that resource declines.

Generalist Predator

A predator with a broad, flexible diet capable of switching among alternative prey species based on relative abundance, enhancing survival amid environmental fluctuations.

Ambush (Sit-and-Wait) Predator

A hunting mode where a predator remains stationary and concealed until prey comes within striking distance, relying on sensory acuity, rapid strikes, or lures.

Ballistic Interception

A predatory strategy where an animal predicts the future spatial trajectory and velocity of moving prey and targets that projected future location rather than current position.

Pursuit Predator

A predator adapted for high-speed chases over distance, relying on sustained locomotion, rapid acceleration, and sensory coordination to run down prey.

Lure

A morphological structure or behavioral display used by a predator to visually or chemically mimic prey food items and draw potential prey within strike range.

Turning Gambit

The hypothesis proposing that agile, smaller prey can successfully evade larger and faster predators by making sharper, tighter directional turns than the predator's higher momentum allows.

Co-evolutionary Arms Race

The reciprocal, iterative cycle of evolutionary adaptations and counter-adaptations driven by natural selection between interacting predators and prey or hosts and parasites.

Free-Rider (Cheater)

An individual in a cooperative social group that gains access to collective group benefits, such as captured food kills, without expending personal energy toward hunting or risk.

Camouflage

Visual coloration, patterning, surface texture, or motionless behavior that prevents an organism from being detected against its natural background.

Convergent Evolution

The independent evolution of similar morphological or behavioral features in distinct, unrelated lineages exposed to analogous ecological selective pressures.

Aposematism

Conspicuous warning signals (such as bright coloration, pungent odors, or alarm sounds) that advertise an organism's toxic, venomous, or unpalatable defenses to potential predators.

Batesian Mimicry

An anti-predator adaptation where a harmless, palatable species evolves to mimic the conspicuous warning signals of an unrelated, noxious or defended species to deceive predators.

Müllerian Mimicry

An evolutionary phenomenon where multiple unpalatable, harmful, or defended species converge on a shared warning signal, reinforcing predator learning and reducing total losses per species.

Dilution Effect

A group-level defensive advantage wherein an individual's statistical probability of being targeted and killed in an attack decreases as the total group size increases.

Selfish Herd

An individual-level behavioral strategy where group members maneuver toward the spatial center of an aggregation, thereby pushing surrounding herd mates to the more exposed outer perimeter.

Confusion Effect

A defensive benefit occurring when the simultaneous erratic movement of numerous schooling or swarming prey animals visually impairs a predator's ability to isolate a single individual.

Predator Naivety

The absence of appropriate anti-predator avoidance behaviors or antipredator responses in prey species exposed to novel or historically absent predators.

Parasite

An organism that lives in or on another living organism (the host), deriving metabolic resources at the host's direct nutritional or physiological expense without immediately killing it.

Host

A living organism that provides the necessary physical habitat, protection, and metabolic nutrients required by a parasite.

Microparasite

A small parasite (such as a virus, bacterium, or protozoan) that reproduces and multiplies directly and rapidly inside its host, typically characterized in populations by infection prevalence rather than individual counts.

Macroparasite

A relatively large parasite (such as a helminth, tick, or flea) that typically does not multiply within the definitive host, has complex life stages, and can be counted individually to assess infection intensity.

Vector

An organism, often an arthropod such as a mosquito or tick, that actively transmits an infectious pathogen or parasite from one host to another.

Definitive Host

The specific host organism in which a parasite matures into its adult stage and carries out sexual reproduction.

Intermediate Host

A required host organism that supports the developmental or juvenile life stages of a parasite, where asexual multiplication may take place without sexual reproduction.

Paratenic Host

An optional transport host in which a parasite survives and remains infective without undergoing any obligatory structural development or multiplication.

Monoxenous (Direct) Life Cycle

A parasitic transmission cycle that is completed using only a single host species across the parasite's entire lifespan.

Heteroxenous (Indirect) Life Cycle

A multi-host parasitic life cycle requiring progression through two or more distinct host species (intermediate and definitive) to complete developmental and reproductive phases.

Host Manipulation

The adaptive alteration of host behavior, physiology, or morphology by a parasite to increase the likelihood of transmission to its next host.

Zoonosis

An infectious disease caused by pathogens that naturally spill over and transmit from vertebrate animal populations into human hosts.

Spillover

The transmission event wherein a pathogen moves from its natural reservoir host species into a novel, previously uninfected host species.

One Health

A collaborative, transdisciplinary framework recognizing that the health of humans, domestic and wild animals, and ecosystems are closely interconnected and interdependent.

Kleptoparasite

An organism that opportunistically steals food, prey, or nesting resources captured or collected by another individual rather than foraging independently.