Humans have a lot of homologous structures in common with other animals, and several of these structures are no longer in working order in human bodies. These nonfunctioning structures are called vestigial structures. They still show evidence of common ancestry, but they do not do the same things in humans as they do in other animals.

Listed below are mostly vestigial structures. Select the one that serves a purpose in humans.

(1 point)
Responses

hair raising: goosebumps in humans versus raising hackles to appear larger and aggressive in other animals like cats and monkeys
hair raising: goosebumps in humans versus raising hackles to appear larger and aggressive in other animals like cats and monkeys

tail: tail bone in humans versus long tails for balance and communication in other animals like lizards and wolves
tail: tail bone in humans versus long tails for balance and communication in other animals like lizards and wolves

pelvis: supports upper body and attaches to lower body in humans versus being tiny and nonfunctional in legless animals like whales and snakes
pelvis: supports upper body and attaches to lower body in humans versus being tiny and nonfunctional in legless animals like whales and snakes

ear muscles: ability to wiggle ears in humans versus rotating ears to hear predators in prey animals like deer and rabbits
Which animal is a vertebrate?(1 point)
Responses

octopus
octopus

shrimp
shrimp

crab
crab

fish
fish
Fish, amphibians, reptiles, birds, and mammals have similar embryos.
They all start with gill slits. Fish and some amphibians grow to have gills. Some amphibians, reptiles, birds, and mammals develop lungs to breathe air.
They all start with tails. Fish, some amphibians, reptiles, and birds grow tails. Humans do not keep their tails.
Fish and reptiles develop scales. Amphibians, birds, and humans have skin. Birds have feathers, and humans have hair.

With which animal do humans exhibit the most linear relationship?(1 point)
Responses

reptiles
reptiles

amphibians
amphibians

birds
birds

fish
What is a homologous structure that humans share with other vertebrates when they are fully grown?(1 point)
Responses

gills
gills

tail
tail

spine
spine

hair

1 answer

  1. The structure that serves a purpose in humans among the options presented is pelvis: supports upper body and attaches to lower body in humans versus being tiny and nonfunctional in legless animals like whales and snakes.

  2. The animal that is a vertebrate is fish.

  3. The animal with which humans exhibit the most linear relationship is amphibians.

  4. A homologous structure that humans share with other vertebrates when they are fully grown is spine.