Adaptations Darwin’s 6th Point!

Types of Adaptations There are 3 broad categories of adaptations: 1) Physiological 2) Behavioural 3) Structural Think PBS!

Physiological Adaptations Involve what is going on inside of the body. Variations in an organisms metabolic and cellular base level processes across a species.

Examples of Physiological Adaptations 1) Antibiotic resistant bacteria 2) Pesticide resistant insects. In each of these 2 cases, some of the organisms of these species developed adaptations that allow them to survive in the presence of the very things that are meant to kill them (antibiotics and pesticides) The members that survived went on to multiply and became the norm.

3) Hibernation of Bears Metabolism slows to ensure that the bear does not starve over the winter. 4) Cows Ruminant Digestive System Allows it to extract maximum nutrition from a less nutrient dense source – such as grass or hay.

Behavioural Adaptations An organisms behaviour may provide it with a better ability to adapt to it’s environment and increase it’s chances for survival. How organisms react and adapt to environmental changes.

Examples of Behavioral Adaptations 1) Seasonal migration by Monarch Butterflies, Birds and Caribou. 2) Hibernation of Bears and Garter Snakes.

3) Bending of Sunflowers towards the sun. 4) Shedding of leaves in the fall by deciduous trees. 5) Animals choosing to stay in the shade when the weather is hot.

Structural Adaptations Structural adaptations involve an organism’s physical make up. Affect the shape or size of features in an organism.

Examples of Structural Adaptations 1) Blowholes of whales and dolphins are relocated nostrils. 2) Needles of cacti are modified leaves that both protect the plant and reduce water loss.

3) Mimicry – Phasmatodea (Walking Stick Insect) 4) Camouflage – (Moth resembles owl)

Can they be both? Adaptations do no always fit neatly in just one of the these categories. Ex) Bear hibernation. Why? Ex) Elephant ears – How can this fit into more than one category?

Follow Up These types of adaptations give an organism an edge in the struggle for food, space, ability to reproduce and the ability to avoid predators. However, environments can change, so what was once an advantage may now be a disadvantage.

Successful (“fittest”) organisms are those with adaptations that allow them to survive and reproduce. Example: Darwin’s Finches!

Acclimatization Don’t confuse adaptation with ACCLIMATIZATION. Acclimatization is when an organism becomes “used to” changes in environmental conditions. This is not the product of natural selection because there is no change in the alleles or gene pools of that species. Ex) Getting used to cold weather in winter.