8-2.1 Explain how biological adaptations of populations enhance their survival in a particular environment. 8-2.7 Summarize the factors, both natural and man-made that can contribute to the extinction of a species.

Variations **There are variations (small differences) among species of similar populations. Some dogs of the same breed have different color fur coats. Example: A golden retriever may have red, blonde, or gold colored fur. Organisms of a species differ from one another in many if their traits.

Adaptations **An adaptation is a trait that helps an organism survive and reproduce.

Structural adaptations A structural adaptation involves some part of an animal's body. Teeth Body coverings    Movement A structural adaptation involves some part of an animal's body, such as the size or shape of the teeth, the animal's body covering, or the way the animal moves.   Teeth - since different animals eat different things, they don't all have the same kind of teeth Body coverings - Hair, scales, spines, and feathers grow from the skin.  All of these parts help animals survive in their environments.   Movement - animals find food by moving from place to place

Protective Coloration Coloration and protective resemblance allow an animal to blend into its environment.  Another word for this might be camouflage.  Their camouflage makes it hard for enemies to single out individuals.  

Behaviour adaptations Behaviour adaptations include activities that help an animal survive.  Behaviour adaptations can be learned or instinctive. Social behaviour   Behaviour for protection   Behavior adaptations include activities that help an animal survive.  Behavior adaptations can be learned or instinctive. (a behavior an animal is born with). Social behavior - some animals live by themselves, while other live in groups.  Behavior for protection -  An animal's behavior sometimes helps to protect the animal.  For instance the opossum plays dead.  A rabbit freezes when it thinks it has been seen. 

Mimicry Mimicry allows one animal to look, sound, or act like another animal to fool predators into thinking it is poisonous or dangerous.   Coral snake (left) very poinsonous & Milk snake (right)

Natural Selection **Natural selection explains this survival and shows how species can change over time. For example, certain traits or adaptations involving color, camouflage, food gathering (beaks and claws) and other physical traits, sensory abilities, or behaviors enhance the survival of a species.

Natural Selection

Natural selection

Natural Selection

Small differences in traits of a species are called A. variations B. adaptations C. natural selection

A trait or behavior that helps an organism survive and reproduce is called: A. variation B. adaptation C. natural selection

A process that explains survival of a species and how a species can change over time is called: A. variation B. adaptation C. natural selection

A species is extinct if no members of that species are still alive A species is extinct if no members of that species are still alive. Most organisms that have ever lived on Earth are now extinct. Natural factors can cause extinctions such as has happened throughout Earth history. Man-made factors have caused extinctions in more recent times, such as the cutting of the rainforest regions, removing natural habitats, over-harvesting, and pollution.

**Natural factors that cause extinctions: Volcanoes Global warming Global cooling Changes in oxygen levels in seawater Meteorite impact

**Man- made factors Cutting down rainforests Removing natural habitats Over harvesting Removing survival needs

Name three natural factors that cause extinction.

Name three man-made factors that cause extinction.