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.
Which two animals exhibit the most linear relationship?
1. amphibians and fish
2. birds and humans
3. amphibians and reptiles
4. birds and reptiles
3. amphibians and reptiles
Amphibians and reptiles exhibit a more linear relationship compared to the other options as they both start with gill slits and tails, and some amphibians and reptiles develop lungs to breathe air. Additionally, both groups have skin, unlike fish which have scales, birds which have feathers, and humans which have hair.