TED Talk – 5 Fingers of Evolution
1. The ancestors
Using thumbs up and down, this video by Paul Andersen from TED-Ed provides students with a mnemonic device to remember five powerful parts that drive evolution. It is a great video for biology, honors biology or as a review in AP Biology.
It is possible that the number of fingers and toes we have owes its origin to the fish with 5 bones in their pectoral fins who were first able to make it to land. However, it is more likely that this was just a good number and there was no advantage to changing it.
Another factor is gene flow, which occurs when animals move between populations and bring new genes to the population. This is why you can find reddish-brown bunnies in a population of gray ones, for example.
3. The ancestors’ tools
Having five fingers on each hand is a result of evolution, but it wasn’t because it gave us some kind of advantage. It was likely just a random number that happened to be lucky for those fish that had 5 bones in their pectoral fins and made the leap from water to land.
Scientists have discovered evidence of our ancestors using tools. A set of cut marks found on animal bones shows that Australopithecus afarensis used stone tools to kill and butcher animals. This Ancestors: The Humankind Odyssey Tool Guide will help students learn about the importance of these early inventions.
5. The ancestors’ culture
The ancestors’ culture can tell us a lot about how they lived, where they came from, and what their priorities were. We can also learn about what they did and didn’t like, which can help us understand where their values came from and how we might be able to connect with them. For example, the ancestors who had five fingers on their hands likely did so because it was a good number for them. They were a bit more agile than those who had 4 or 6 fingers, so they may have had an advantage in the water. However, this was probably not the only factor that led them to evolve into humans.