Observing Animal Behavior

Scientists have learned about animal traits by observing animals in nature. Jane Goodall is an English scientist who made important discoveries about chimpanzees. She spent many years in Africa, observing the animals in their natural surroundings. She discovered that chimpanzees use objects, such as twigs and rocks, as tools. Scientists now think that this behavior is an acquired trait. Young chimpanzees learn to use tools by watching adults.

Goodall learned that chimpanzees share many other traits with humans. Today she works to protect these animals. She has changed the way we think about chimpanzees - and the way we think about ourselves.

Many physical features are inherited traits. The color of your eyes is an inherited trait. So is the shape of your nose. A ladybug inherits its spots. A dog inherits its sense of smell and having four legs. An apple tree inherits its leaf shape, flower color, and kind of fruit. These are physical traits.

Some physical features change over time. Your hair gets longer unless you get it cut. You grow taller and heavier as you get older. A plant can grow more leaves and longer roots. But inherited traits do not change. Your eyes will always be the same color they are now. The fruits of an apple tree will always be apples.

A scar is a physical trait that is acquired. An animal is not born with a scar. A scar forms after an animal is injured. Plants, too, can acquire traits. A tree may become bent by the wind or scarred by lightning.

Acquired physical traits are not passed from parents to their young. A deer that gets a broken leg will not have a fawn with a broken leg. The acorn of a an oak tree burned by lightning will not grow into a tree with the same burn.

The lists below gives examples of physical traits that are inherited and acquired. You may think of examples to add.

Inherited Physical Traits

A girl has brown eyes

A boy has curly hair

A horse has four legs

A plant has red flowers

Acquired Physical Traits

A girl has a bruise on her hand.

A boy's teeth are straightened with braces

A horse has a bump on its leg where the leg was broken.

A plant's leaves have spots from a disease.