Bird Beak Lab

In this lab we were asked the question, "How do changes in selective pressures affect the evolution of that species?" We found that through natural selection, and through different beaks, that the population changed to have significantly more spoon billed birds. Our data clearly showed that the spoon beaked bird had the most offspring. The spoon beaked bird had 26 offspring, the binder clip beak had 20 offspring, the tweezer beaked bird had 12 offspring, and the scissored beaked bird had 14 offspring.  The spoon billed beak made up 36% of the total offspring and the binder clip beak made up 27%, but non-the-less the spoon billed bird still had the most offspring. This data supports our claim because the trait of the spoon birds had extended through the population in such a short amount of time and the population had begun to look like them, or the "winners".

Some potential errors that we could have had would definitely be the variation in the amount of food. Obviously, some of the beaks were better suited to picking up different types of food. Some group had many rubber band seeds, and some had many macaroni seeds etc. For example, I found that picking up rubber band seeds and the macaroni seeds were most easy as I played the spoon billed bird. Our group in particular had many many rubber bands and that is partly why the spoon billed bird excelled in the kind of environment. Another potential error that we could have had could have been the amount of offspring produced per food. We had one offspring for every 5 pieces  of food that were collected, and the second time for every 10. This is not a real example of what would happen is the real ecosystem. 10 pieces of food does definitely not guarantee one a healthy offspring. There could have been a lot of variation, like the bird not being able to find a mate, or maybe the ecosystem was out of balance and there were to many predators.

This lab was done to demonstrate how natural selection and changes in the environment can affect the evolution and traits of a population. I learned from this lab that there are many different variables that help contribute to making just one offspring. Also, just one trait of a species chooses how successful they are in surviving. Based on my experience from this lab, I now know that evolution is really not such a complicated process. It is really just natural selection, and the kind of ecosystem.

Graph #1

                    Graph #2

Different kind of bird beaks