Species Interactions: Predation

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Which of the following describes a type of predation where the predator is an animal and the prey is a plant?

Carnivory

Omnivory

Herbivory (correct)

Parasitism

Carnivores typically do not kill their prey immediately.

False

What is one key adaptation that predators have developed to maximize their hunting success?

Camouflage

In the interaction where a predator consumes prey that are both animals, it is known as __________.

carnivory Signup and view all the answers

Match the following types of predation with their definitions:

Carnivory = Predator and prey are both animals Herbivory = Predator is an animal and prey is a plant Omnivory = Predator can be an animal or plant consuming animals and plants Parasitism = Predator is a parasite feeding off a host Signup and view all the answers

What does the constant 'a' in the Lotka-Volterra model represent?

The efficiency of predators capturing prey Signup and view all the answers

Predators will always grow exponentially in the presence of prey.

False Signup and view all the answers

What happens to predator populations when there is a complete absence of prey?

They decrease exponentially due to starvation. Signup and view all the answers

When predators are absent, prey populations exhibit __________ growth.

exponential Signup and view all the answers

Match the variable to its meaning in the Lotka-Volterra model:

N = Number of prey individuals P = Number of predator individuals r = Growth rate of prey m = Mortality rate of predators Signup and view all the answers

According to the Lotka-Volterra model, what happens to the predator population when prey are present?

It increases based on prey encounters. Signup and view all the answers

Anolis lizards were used in a case study to examine the effects of predation.

True Signup and view all the answers

What do researchers Thomas Schoener and David Spiller aim to investigate in their study with Anolis lizards?

The community level effects of predation on spider species diversity. Signup and view all the answers

What is a common adaptation for predators when hunting prey?

Speed Signup and view all the answers

Most carnivores are specialists and most herbivores are generalists.

False Signup and view all the answers

Name one type of adaptation a predator might use to avoid being eaten.

Large size or speed or body armor or toxins or mimicry or crypsis Signup and view all the answers

Herbivores tend to feed on specific parts of their plants, usually where there is the most ______.

nutrition Signup and view all the answers

Match the features with their respective categories:

Predators = Hunt or wait for prey Herbivores = Eat plant parts with high nutrition Carnivores = Avoid being eaten Herbaceous plants = Produce chemicals as defenses Signup and view all the answers

Which of the following is a method herbivores use to reduce predation?

Inducible defenses Signup and view all the answers

The snowshoe hare and lynx exhibit predator-prey population cycles.

True Signup and view all the answers

What is one way plants can outsmart seed-eating herbivores?

Produce a lot of seeds or time the release of seeds Signup and view all the answers

Study Notes

Species Interactions: Predation

Predation is a trophic interaction where one species, the predator, consumes another, the prey.
Predation includes carnivory (predator and prey are both animals), omnivory (animal or plant predator, and animal/plant prey) and herbivory (animal predator eating plant prey). Parasitism (parasite predator and host prey) is also included.
Carnivores typically kill their prey. Herbivores, however, usually do not kill the plants.

Key Differences Between Carnivores and Herbivores

Carnivores often kill their prey immediately, while herbivores usually do not kill the plants directly.
Animal prey can move away or hide from predators, often escaping. Most plant prey cannot hide or escape.
Plant prey is usually plentiful but less nutritious compared to animal prey because they have lower nitrogen content.
Carnivores are generally generalists while herbivores are often specialists, feeding on specific parts of plants or prey.

Carnivory

Carnivory is the consumption of animal prey by an animal predator.
Adaptations for hunting include stealth (owls), speed (cheetahs), morphological adaptations (snakes), and venom (vipers).
Predators who sit and wait employ adaptations like building traps (antlions) and mimicry (scorpionfish).

Herbivory

Herbivory is the consumption of plants by animals.
Adaptations for herbivory include behavioral adaptations (e.g., Bursera beetle larvae) and digestive tracts that accommodate secondary compounds or mechanical deterrents (e.g., spines).

Predator-Prey Population Cycles

The Lotka-Volterra model, dN/dt = rN – aNP and dP/dt = baNP− mP, assesses predator-prey population dynamics. In the equation, N is the number of prey individuals, and P is the number of predator individuals.
When predators are absent, prey should experience exponential growth.
When prey are present, the predator population will increase proportionally to the amount of prey available. The efficiency with which predators capture their prey is a factor in their population increase, signified by the constant a.
Predators starve if no prey is present; thus, their population declines exponentially if there's no prey, and a mortality rate is involved.

Effects of Predation on Communities

Carnivores and herbivores can change the composition of a community.
Case study examples include Anolis lizards in the Bahamas and Lesser snow geese.
Intermediate grazing has a positive effect on the community, resulting in the highest Net Primary Productivity (NPP). Abundant prey leads to an increase in predators, which in turn lowers prey numbers. This causes the prey population to decline while the predator population increases.
However high prey populations can also have a detrimental impact on the community. For example, the rise of the snow goose population led to a significant decline in plant life and made the marshes into mud flats.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

This quiz explores the concept of predation, a vital trophic interaction where predators consume prey. It covers various types of predation, including carnivory, herbivory, and the differences between carnivores and herbivores. Test your understanding of these ecological dynamics and their implications in food webs.