Lecture 19

Question 1

Mutualism

Answer 1

Interspecific interaction that benefits both species (+/+)
Ex) -Plants and their pollinators
-Nitrogen fixing bacteria and plants
-mycorrhizal fungi and plants
-seed dispersers and plants

Question 2

Commensalism

Answer 2

Interaction between species that benefits one of the species and neither harms nor helps the other (+/0)
Ex) - Water buffalo and cattle egrets
-epiphytic plants and host trees

Question 3

Species interactions are dynamic and conditional

Answer 3

-relationship between water buffalo and egrets is normally mutualistic but if egrets begin removing parasites from water buffalo then it becomes mutualistic

Question 4

Why do we care about species interactions?

Answer 4

1) Understanding the natural world

2) Understand, predict and control consequences of anthropogenic effects

Question 5

Keystone Species

Answer 5

A species that has an exceptionally great impact on the other species in its ecosystem relative to its abundance

Question 6

Keystone predators

Answer 6

sea otters, wolves, sharks

Question 7

Keystone mutualists

Answer 7

seed dispersers, pollinators, fungi

Question 8

Keystone habitat engineers

Answer 8

Beavers, elephants, kangaroo rats