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Adapting to the Environment. Section 3.2. Adaptations of Organisms. We have just finished studying 8 areas in the biosphere that have different climates and environmental conditions. We called these areas biomes .
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Adapting to the Environment Section 3.2
Adaptations of Organisms • We have just finished studying 8 areas in the biosphere that have different climates and environmental conditions. • We called these areas biomes. • Today we will focus on the adaptations that organisms must have in order to survive the environments that these biomes provide.
Adaptations of Organisms • What is an adaptation? • Any trait that an organism has that improves its chances of survival. • There are adaptations that affect and/or are influenced by both the biotic and abiotic environments of the organisms.
Adaptations of Organisms • Examples: • Turtles • Abiotic adaptations: (help with life in water) • Eyes/nostrils high on head • Paddle shaped feet and skin between toes • Biotic adaptations: (help escape predators) • Swims with most of its body under water • Hard shell for protection
Adaptations of Organisms • Examples: • Arctic Fox: • Abiotic adaptations: (for the cold temperatures) • Thick coat of fur • Biotic adaptations: (to help escape predators) • White coat to blend in with environment
Adaptations of Organisms • Examples: • Hawk: • Abiotic adaptations: (to help fly) • Light, hollow bones • Wide wing span for soaring • Biotic adaptations: (to catch prey) • Keen eyesight to spot prey • Sharp beak and claws • Fast movement to catch escaping prey
The Process of Natural Selection • When you think of Natural Selection there is one phrase that you need to remember: “Survival of the fittest.”
The Process of Natural Selection • This means that: • Nature selects only the best adapted organisms to survive and reproduce while the least fit are eliminated.
The Process of Natural Selection • Nature selects only the best adapted organisms to survive and produce offspring. • How do these organisms acquire these important adaptations?
The Process of Natural Selection • These traits are passed down from generations to generation through genes that are inherited from parents. • They are not acquired by the organism in order to survive. “Adaptation happens by chance, not by choice.”
Natural Selection & Predation • Natural Selection will favour the best adapted predators as well as the best adapted prey. • There are a few common mechanisms that have been observed…
Natural Selection & Predation • Camouflage: • This is an adaptation that allows the organism to hide from predators, or to increase the chance of finding prey.
Natural Selection & Predation • Warning Coloration: • Organisms develop a colour that warns potential predators that they might be poisonous. • A.K.A. aposematic coloring
Natural Selection & Predation • Mimicry: • When one species has evolved a resemblance to another poisonous/dangerous/distasteful organism.
Natural Selection & Predation • Coevolution: • Predator and prey evolve structures in response to each other’s adaptations. • As one organism changes (evolves), so does the other.
Biodiversity • Biodiversity: • The wide variety of living organisms and the variation among organisms. • The higher the primary productivity (productivity of producers) the more biodiversity there will be.
Biodiversity • Ecosystems with low primary productivity tend to be the fragile ecosystems. • This is because there are few species to begin with, so the removal of any species can be devastating to the ecosystem.
Keystone Species • A keystone species is any species whose removal from an ecosystem can result in the collapse of the entire ecosystem. • The sea otters that live off the west coast of Vancouver Island are a good example, see page 65 in your book.
Keystone Species • This is their food chain:
Keystone Species • For the rest, we need to know two definitions: • Extinction: • When a species is completely gone from the Earth • Extirpation: • When a species is removed from one area
Keystone Species • What happened to the food chain when the otter population was nearly extirpated?
Keystone Species • Explain how the problem was solved in the late 60’s and early 70’s.