160 – Serengeti CER and the Snickers Bar of the Desert

Today in honors biology we took a simple pencil/paper activity and used it to do a Claim, Evidence, Reasoning (CER). The kids were using the activity as an assessment for one of their learning objectives. I had already used Doctopus to send them a template for their Google drive for the final copy. In class, they were to collaborate and work together to answer the questions about the activity which described multiple herbivores visiting the Serengeti, effectively following the rains and partitioning the niche unbeknownst to each other. During the work time, they were to complete the explanation tool for the CER. They were given the essential question “How do herbivores interact with each other on the Serengeti?” They were to create a claim to answer the question, pull out evidence form the data, tie classroom science to each piece of evidence, and write a reasoning statement that supported the claim, with the evidence and backed by science. In 15 minutes they actually did really well. The hardest part is backing the evidence up with our classroom science. Synthesis is hard for them since they are very literal beings right now. 

In AP biology we used our second model organism, the Rock Pocket Mouse, to study the effects of a selective pressure (visual predators) on the coat color phenotypes present in the population on tan desert terrain, and black lava flows. The students were given 4 pictures with two terrains (tan and black) and in each there were a number of mice. They were to sequence the pictures in a way that made evolutionary sense. They then watched one of the best 15 minute educational films made for biology, concerning the natural selection of the Rock Pocket Mouse (nicknamed the “Snickers bar of the desert”). High drama. 

The students were to think about how a random mutation (dark coloration), was a selective advantage in some environmental circumstances and a detriment in others. When it was an advantage, they had to think about how a mutation like this would spread rapidly in the population in a short period of time, while in the non-adaptive terrain it was selected against. They also had to ponder the idea of convergence on a specific phenotype since other, unrelated, Rock Pocket Mouse populations distally to these had similar mutations caused by different mutated genes. 

Tomorrow the honors kids will learn about the beaver as a keystone species through a card sorting game and the AP kids get a nice, old fashioned lecture, broken up by some short activities. 



Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s