In an incredible research study, scientists studied juvenile bichir (a type of fish) on land to understand the evolutionary changes that may have taken place about 400 million years ago. That’s right- teaching fish how to walk is teaching researchers about evolution! These African fish are unique because they have lungs AND gills, and juveniles will sometimes walk on their fins. Researchers believe that bichirs walk in a way that is similar to early tetrapod ancestors.
When scientists looked at the differences in walking ability between bichirs raised in an aquatic environment versus bichirs raised in a terrestrial environnment, they found that the terrestrial animals became much more efficient at walking. What’s more, their anatomy began to change to facilitate walking!
Watch the video here- it’s interesting!
This research suggests that organisms’ anatomy is changed in response to environmental changes. This is called developmental plasticity. The theory is that developmental plasticity gave early ancestors of tetrapods the ability to walk onto land. Once in a terrestrial environment, the animals were forced to evolve more quickly to keep up with the environment.
This research is amazing, because scientists pretty much created a snapshot of evolution right in the laboratory! They also provided a pretty good basis for the argument that plasticity was important in the evolutionary steps that led to walking. Read more about it here: http://www.nature.com/news/how-fish-can-learn-to-walk-1.15778