Chapter 54 Co-Evolutuon & Species Interactions

Question 1

What are the consequences of different species interacting with one another? In other words how might species affect one another in general?

Answer 1

• affects each others fitness/genotype frequencies
• ecological consequences: influence population densities and species distributions
• evolutionary consequences: development of adaptations and evolutionary change in one species

Question 2

What is co-evolution?

Answer 2

Adaptations in one species may lead to reciprocal adaptations in a second species it interacts with

Question 3

How do different species affect the structure of a community?

Answer 3

Increase in one species affects the abundance of other species

Ex: bird feeds on caterpillars. Directly benefits bird, directly affects caterpillars. Indirectly benefits trees because caterpillars eat trees

Question 4

Mutualism (+/+)

Answer 4

Both species benefit

Ex: se anemone and clownfish: anemone-fish attacks predators and fish’s feces serve as nutrients. Fish-anemone gives protection sting cells of anemone does not affect fish

Ex: térmite and gut microbes tryconympha
Termite-microbes break down cellulose. Microbes get a place to live and nutrients

Question 5

Commensalism (+/0)

Answer 5

1 species benefits the other is not affected

Ex: ferns,epiphytes,trees. Fern benefits from getting on a perch of tree and gets sunlight, tree is not harmed

Ex: sharks and remoras, remoras attach to shark for transportation and eats on left over food from shark and feeds on sharks feces

Question 6

Ammensalism (0/-)

Answer 6

One species is unaffected while the other is harmed, doesn’t realize they’re harming

Ex: elephants step on grass (0) plants and insects get crushed (-)

Question 7

Competition (-/-)

Answer 7

Both species harmed, each gets less of that resource than they would if they lived alone without competition

Interspecific: competition between different species
Intraspecific: competition between the same species

Question 8

Interspecific competition

Answer 8

Competing for a food source
-scavengers same prey/food source direct competition for that prey kill made by one species may be stolen by another

Plants: compete for light and soil

Question 9

Intraspecific competition

Answer 9

Compete for mates, food, and territory

Question 10

Predation (+/-)

Answer 10

1 species (predator) benefits and prey does not

Question 11

What is the evolutionary arms race?

Answer 11

Predators and prey exerts selective pressure on one another and there are reciprocal adaptations
-mutations give prey advantage for defense and then predator who mutate to preys defense. Back and forth

Ex: prey develops venom, predator becomes resistant to it

Question 12

What are adaptations to predation

Answer 12

Physical or chemical

• thorns are difficult to eat
• insects have toxic chemicals

Question 13

What is aposomatism?

Answer 13

Warning coloration to predators, they’re dangerous or poisonous. Venom is costly to produce so use color as warning

Question 14

What is mimicry? How does Batesian mimicry differ from Mullerian mimicry?

Answer 14

One species resembles another which is deadly to avoid predation

Ex: snakes-red on yellow hurts a fellow, red on black is a friend of jack

Batesian: a non toxic edible species (mimic) looks like a toxic species (model) benefit avoidance behavior learned by models predators physical or behavioral

Mullerian: a number of aposematic species converge in a common color pattern. All species share this color pattern and live together in the same region

Question 15

What is crypsis?

Answer 15

Species appearance helps it blend into the surroundings to avoid predation (camouflage)

Question 16

Parasitism (+/-)

Answer 16

One species the parasite,parasitoid benefits while the host is harmed. Parasite doesn’t kill the host because it takes nutrients. The host can get sick becomes vulnerable to predation and not attractive to mates

Question 17

Parasitoid

Answer 17

Free living insects that lay eggs in other insects or larvae on insects

Ex: cricket and parasitoid fly. Female flies listen for cricket songs and she lays eggs inside cricket. Babies eat the cricket from inside out and then hatch out of them

Question 18

What is a niche? How is it defined?

Answer 18

Set of physical abiotic and biological biotic conditions required by a species. Where it survives grows and reproduces

-defined by resources available and interactions with other species (competition)

Question 19

Difference between a fundamental niche and realized niche

Answer 19

• fundamental: full range of environmental conditions where a species can live (defined by physiological capabilities)
• realized niche: where and how a species actually lives. Subset of fundamental niche and is defined by its interactions with other species

Question 20

What is competitive exclusion?

Answer 20

Two species competing for limited resources. One will be superior and outcompete the lesser and will be pushed out

Question 21

What is resource partitioning?

Answer 21

Over time competing species may evolve to lower competition so they don’t have to compete

Ex: lizards live at different elevations in tree so they take food from different areas

Question 22

How does competitive exclusion and resource partitioning differ?

Answer 22

-competitive exclusion they compete someone will get pushed out, partitioning they’re not really competing

Question 23

What type of interactions are involved with the example of the leaf cutter ants farming fungus?

Answer 23

Symbiotic/mutualistic relationship. Ants use leaves ad fertilizer to grow their fungus. The ants larvae eat the fungus