Natural Selection

Natural SelectionANI

MAL ADAPTATIONS

What is natural selection?This is the idea that a living thing has something that makes it more likely to survive . Some researchers believe that language was created in order to help humans survive. A group of hunters communicating to become more effective is one example of how this could happen. If a living thing lacks a certain trait that will allow it to survive, there are two options: 1) species dies out2) it develops the missing trait.

This process results in ADAPTATIONS, A body part, body covering, or behavior that helps an animal survive in its environment.

We all have adaptations that allow us to survive. Can you think of any?

Body PartsMany animals have developed specific parts of the body adapted to survival in a certain environment (area). Among them are webbed feet, sharp claws, whiskers, sharp teeth, large beaks, wings, and hooves.Webbed FeetTo aid swimming, many animalshave webbed feet. Webbed feet help animals move through the water with ease. This can help the animal swim faster to catch prey or escape a predator.

Whiskers They serve as an important purpose for many animals. Whiskers around the face, specifically the mouth area, help the animal feel its way through tight spots. In a way, they serve as"feelers," telling the animal whether or not it can fit into a specific area.

Body CoveringsAn animal’s body covering is an adaptation. • Mammals have hair, or fur, that helps insulate their bodies (keep

them warm). • Birds also have a very protective covering: feathers. The feathers

keep the bird warm in winter, help it fly or swim, and help fan the bird in hot weather. • Amphibians and reptiles have body coverings that protect them as

well. Amphibians have moist, slick skin that is well suited for the water. Reptiles have tough, dry skin covered by scales.

Striped Fur• Striped fur is one variation of a special adaptation called

camouflage. • Striped fur, in most cases, helps animals blend into their

environment. • Striped fur, like a tiger, helps it match the area around it making it

nearly invisible to other animals. • In other animals, like the skunk, the stripes serve as a warning to

predators.

Spotted Fur• Another adaptive type of body coloring is spotted fur. Spotted fur

is similar to striped because it is camouflage.• One example is the jaguar, which lives in the rain forest. The

jaguar's spotted fur helps it blend in with the small patches of sun that reach the rain-forest floor. These patches, mixed in with the shade, look like a jaguar's coat• Another animal with spotted fur is the snow leopard. The snow

leopard, with a white coat and black spots, lives in wooded areas as well, using its coat to hide in the trees and snow.

Scales• Scales are protecting animals from the environment.• In the case of other snakes, the climate may be dry and the

land sandy and rocky; and their skin would be destroyed without scales.

• Scales help protect the body of the animal where skin, fur, or feathers would become damaged or destroyed.

Habitats

• Organism- one living thing– The organism needs to obtain food, water, shelter

and other things to survive, grow and reproduce from its surroundings.

• Habitat – The place where an organism lives to fulfill those needs. (an animals home)

Limiting Factors• When conditions are good a population will

generally increase. However, it cannot grow forever.• Limiting factor- an environmental factor that

prevents a population from increasing. – Food: Sometimes there isn’t enough food. – Space: usually a limiting factor for plants (not enough

room to grow and expand)– Weather: flood, hurricane, frost, temperature

• Carrying capacity: the largest population that an environment can support. For example when we did the science lab “how many bears” we found at most only 25 bears could live in the area if the food was divided evenly.