Environmental Relationships/Introduction to Biomes
Voc. List: Habitat, Niche, Specialized species, Generalized species, Competition, Predator, Keystone
Predator, Prey, Competitive exclusion, Evolution, Convergent Evolution, Artificial selection, Adaptation,
Behavioral Adaptation, Mimicry, Structural Adaptation, Camouflage, Warning coloration, Resistance,
Pesticide, Symbiosis, Parasitism, Commensalism, Mutualism, Coevolution, Biomes
Relationships in the Ecosystem
Habitats and Niches
Habitat-Where an organism lives
Niche-The role of an organism plays within an ecosystem
 Includes biotic and abiotic factors
o Specialized species-an organism with a small niche and generally eats only one
thing.
 Vulnerable to extinct
 Example-Koalas only eat the leaves of eucalyptus trees and Panda bears
only eat bamboo
o Generalized species-An organism with a wide niche
 They have several food sources
 Examples: Mice and cockroaches
Competition-is a relationship in which more than one species attempts to use the same limited resource
Predator-is an organism that actively hunts other organisms
 Keystone predator-A predator that promotes a great niche diversity in its habitat
Prey-The organism that is hunted
 Predator plays an important role in increasing niche diversity by decreasing the
population of the prey population
Competitive exclusion-extinction of a population in one area only
Evolution and Adaptation
Evolution-is a change in the characteristics of a population of organisms over time.
 Convergent Evolution-The independent development of similar adaptations in two
species with similar niches.
o Example:
 The wings of birds and bats

Artificial selection-The selective breeding of organisms by humans for a specific
characteristic/s.
o Examples: dogs, fruits, vegetables, and grains
1


Humans bred wolves over time to produce the dogs we have today.
Humans are saving the seeds from the largest and sweetest fruits and
the most nutritious grains. Then the farmers use those seeds to plant
the next batch to insure they are going to get the best products.
Adaptation- the ability to change to be able to live in an environment either by structural changes or
actions
 Two types of adaptation
o Behavioral-instinct or actions
Examples:
 Mimicry-Harmless species having the same behavior of a species that
has a chemical protection.
 Example: Harmless insect acting like a bee or a wasp
 Squirrels gathering acorns so it has food in the winter is an example of
an action
o Structural-bodily change
 Camouflage –disguising their recognizable features
 Example: In the winter time the Arctic hare has white hair to
protect itself from predators
 Warning coloration-Alerts potential predators to stay away and protects
the prey species from damage
 Examples:
o Patterns with black stripes and red, orange, or yellow
are common in several species of wasps, bees, snakes,
skunks, and poisonous frogs
 Evolution of Resistance-unwanted Adaptations
o Resistance-the ability of one or more organisms to tolerate a particular chemical
designed to kill it.
 Examples:
 Plant diseases being resistance to pesticides (a chemical
substance created to kill insects or other pest on plants)
 Bacterial and Fungal diseases becoming resistance to
Antibiotics
Symbiosis and Coevolution
Symbiosis is the close permanent relationship between different species for survival.
There are three types:
1. Parasitism– When one species benefits (parasite), and the other is harmed-the host
 Example: tick (parasite) on a dog (host)
 Parasites do not usually kill the host as it would leave them without a food source
2. Mutualism – When both species benefit from the relationship
 Example: ants and acacia tree
3. Commensalism – When one species benefits and the other is neither harmed or benefited
 Example: moss growing on trees)
2
Coevolution-The process where species that interact closely together adapt to each other’s existents
and sometimes depend on one another for survival
Examples:
 The acacia tree is benefited because the ants attack any organism (by either
killing it or driving it away) that lands on the tree and the ant clears away the
vegetation near by the tree so the tree can get the proper amount of sunlight.

Hawaiian honeycreeper has a curved beak so it can retrieve the nectar of the
lobelia flower and the flower gets pollinated during the process by the pollen
being forced on the bird’s head from the last flower it visited
3