4.9 Variation in Color Perception among Humans and Animals

A set of flashcards designed to help review key concepts related to color perception and deficiency in humans and animals.

What is the common misconception about color blindness?

Color blindness is often referred to, but it is actually color deficiency.

What type of color vision do most people have?

Most people have normal trichromatic vision, which involves three types of cones.

What is dichromatism?

Dichromatism is a condition where an individual has only two cone types instead of three.

How is color deficiency diagnosed?

Color deficiency can be diagnosed using color vision tests, such as those showing numbers embedded in colored images.

What percentage of males have color deficiency compared to females?

Approximately 8% of males have color deficiency, while only about 0.05% of females do.

Why is color deficiency more common in males?

Color deficiency is more common in males because the gene for normal color vision is on the X chromosome, and males have only one X chromosome.

What type of color vision do marine mammals like sea lions have?

Marine mammals like sea lions are usually monochromatic, having only one type of cone and seeing mostly in black and white.

What is the typical color vision of dogs?

Dogs are dichromatic, meaning they have two cone types and see a limited range of colors compared to humans.

What type of color vision do most birds possess?

Most birds are tetrachromatic, having a fourth cone type that allows them to see ultraviolet light.

Why do crows and ravens appear black to humans?

Crows and ravens have UV patches in their feathers that reflect ultraviolet light, which humans cannot see.