Lecture Six Flashcards
(33 cards)
What are the three main types of species interactions?
Predation, competition, and symbiosis.
What does predation result in?
A positive outcome for one individual and a negative outcome for another.
What are three types of predation?
Carnivory, herbivory, and parasitism.
What is carnivory?
An usually lethal form of predation.
What is herbivory?
A typically non-lethal (but resulting in harm) form of predation.
What is parasitism?
A typically non-lethal (but resulting in harm) form of predation.
What is Coevolution?
When a one species acts as a selective force on another species, and the counter adaptation of the second species, in turn, affects the first species.
How do predators and prey undergo coevolution?
Predators are strong selective forces on their prey. As predators adapt to prey, natural selection also shapes the prey’s defences.
How have the Heliconius caterpillar and Passionflower plant coevolved?
Prey adaptations:
1) Toxic to most insects
2) Sugar deposits mimic eggs of Heliconius,
3) Scent of sugar attracts predators of Heliconius
Predator adaptations:
Plant is not toxic to Heliconius.
What is Stalking Predation?
An adaptive predation strategy relating to speed; for example, a cheetah chasing a gazelle.
What is Pursuit Predation?
An adaptive predation strategy relating to social coordination; for example, a pack of wolves chasing moose.
What is Ambush Predation?
An adaptive predation strategy relating to morphology and camouflage; the yellow crab spider and the northern pike both exhibit this.
How do plants combat predation?
Plants cannot run from herbivores, so they have adopted physical and chemical defences such as spines, thorns, leathery leaves, thick cuticles, poisons.
How does the Acacia tree combat predation?
It sends chemical signals to other leaves when eaten, causing them to wilt and appear less appetizing.
What are some poisons that plants may produce to defend against predation?
Strychnine, rotenone (used as organic pesticide), or unpalatable compounds like tannins. Milkweed causes a heart attack if eaten.
What physical defences can animals have against predation?
Quills or spines, horns, pincers, stingers (bees), shells (turtle), tough hides, large size, odour repellents, various defensive behaviours, etc.
What is Cryptic Coloration?
A defence against predation in animals, camouflage: colours or marking that help some organisms avoid detection from predators by blending into their surroundings.
What is Aposematic Colouration?
A chemical defence against predation, animals may store toxins to deter predators. These animals are often brightly coloured, so that, predators may quickly identify them.
What is Mimicry?
An attempt to mimic another, an effective defence mechanism.
What are the two types of Mimicry?
Batesian mimicry and Müllerian mimicry.
What is Batesian Mimicry?
The resemblance of a palatable or harmless species to an unpalatable or venomous species.
What is an example of Batesian Mimicry?
Many predators learn to avoid the honey bee which is armed with a toxic stinger; because the flower fly resembles the honey bee, predators will also avoid it.
What is Müllerian Mimicry?
When two unpalatable species that inhabit the same community mimic each other.
What is an example of Müllerian Mimicry?
The cuckoo bee and yellow jacket have stingers and occupy the same communityand both are using similar coloring to signal their painful sting to predators.
This helps predators learn faster than if each had its own distinct coloration.
