The top 10 Vestigial

Structures

10

The Wings on Flightless Birds

• The Cassowary, the sexier, but less-well-known flightless bird. Kiwi bird in Australia.

9

Hind Leg Bones in Whales

• Whale skeleton showing pelvis and thigh bones. Snake hind limbs.

8

Erector Pili and Body Hair

• When a rabbit is scared, its hair stands on end. When a human is scared, he or she calls the police.

7

The Human Tailbone (Coccyx)

• The human tailbone doesn't do much, but really hurts if you land on it.

6

The Blind Fish Astyanax Mexicanusand Blind Mole rat

• Astyanax Mexicanus: growing up in the wrong neighborhood.

5

Wisdom Teeth in Humans

• They need regular brushing but did they come from Apes?

4

The Sexual Organs of Dandelions

• Send in the clones ...

3

Fake reproduction in Virgin Whiptail Lizards (Vestigial Behavior)

• Feminist lizards take the male out of the picture.

2

Male Breast Tissue and Nipples

• They are not fully functional and, because cancer can grow in male or female breast tissue, the tissue can be dangerous.

1

The Human Appendix

• In 2000, in fact, there were nearly 300,000 appendectomies performed in the United States, and 371 deaths from appendicitis.

Analysis

1. Define vestigial.

2. How could vestigial structures be proofs for evolution?

3. Choose 2 of the structures mentioned and give an explanation for why they exist.

Answers

1. Vestigial: “remnant of” structure that is seemingly useless

2. Ancestors may have used that structure. Ex. Appendix was used to help digest high fiber foliage, but now we rarely eat roughage.