Chapter 11 - Community Flashcards
What is the definition of a community?
All of the organisms that live together in the same time and place.
What is an ecological niche?
How the organisms interact with biotic and abiotic elements of their environment. The niche is the lifestyle. (Can describe habitat and interactions with other species).
What is an ecotone?
A place where the environment changes abruptly.
What are fundamental and realized niches? Give an example.
The fundamental niche is the dream lifestyle. Realized niche is the actual lifestyle.
An example is with barnacles living higher or lower on the rocks.
What is competitive exclusion?
What is the remedy to competitive exclusion?
Where one species will kill the other by competition.
The remedy is resource partitioning.
What is resource partitioning? Give 2 examples.
Resource partitioning is where species will adapt to no longer be in competition with one another.
An example is with lizards, where different species will inhabit different parts of the tree so that they do not compete for food.
Another example is with birds on different islands. When they live on separate islands, they look very similar, but when they are together, one species will have smaller beaks to eat smaller nuts while the other will have larger beaks to eat different, larger nuts.
These are examples of character displacement.
What are the different defences against predation? Give examples for each.
Camouflage: cameleons.
Chemical defense: plants that are toxic or animals that have poisonous skins. Examples are monarch caterpillars which eat poisonous milkweed and become poisonous themselves. Another example is with cane toads which have skins that secrete poison.
Aposematic colouration: where animals have distinct colouration to warn predators that they are dangerous. Skunks are an examples.
Bastian mimicry: Where a non-dangerous species pretends to be a dangerous one.
Mullerian mimicry: Where different species use the same signal to show that they are dangerous. Bees and wasps are an example.
What is predator-prey coevolution? What are some examples?
It is when predators and prey evolve together. For example:
The hare evolves to run faster to excape the lynx, the lynx evolves to run faster to catch the hares.
Cabbages have evolved to become more and more bitter to protect them against caterpillars, which in turn have evolved to be more and more tolerant to the bitter taste.
What are the three types of species interactions?
Competition (-/-), symbiosis, and predation (+/-).
The different types of symbiosis are:
Mutualism (+/+), commensalism (+/0), and parasitism (+/-).
An example of mutualism is with cyanobacteria and lichen.
An example of commensalism is with skin mites.
An examples of parasites is athlete’s foot.
How do parasites work?
Often, they live in a host, which they do not harm, as the host has evolved a resiliance. This host than transfers the parasite to other species which have no resiliance. This second species is harmed.
Parasites evolve to be less and less harmful, as they do not want to kill their host (otherwise they can no longer take advantage of them).Smallpox in Native Americans example.
What is a keystone species?
A species that is essential to creating a particular ecosystem. Exmple: beavers in wetlands. Sea otters in the sea.
What are primary and secondary succession?
In primary succession, the climax community is eventually created from what started as bare rock.
In secondary succession, the nutrients are already there usually in the soil (ex. fire).
What are the levels of organization in order?
Atoms, molecules, macromolecules, organelles, cells, tissue, organs, organisms, populations, species, communities, ecosystems, biosphere.
