I just discovered this very cool photo comparison tool. I was so excited to use it I pulled out some comparison shots of the vernal pools I study.

It might be surprising, but tree canopies can have major impacts on aquatic amphibians. The greater the canopy cover, the less light will reach a ponds surface. Wood frog tadpoles are adapted for rapid development and every small increase in water temp from every small stream of sunlight can make or break a tadpole’s survival. In addition to temperature, the amount of light incident on a pond dictates the amount of algae growth, which in turn dictates the concentration of oxygen in the water. Also, the amount of algae can dictate how much food competition exists between tadpoles, and how bold tadpoles must be to seek out food. In a pond full of predators, being bold can have dire consequences.

More leaves in the canopy also means more evapotranspiration, which in turn means greater water demand from tree roots. As tree suck water out of the ground, the water levels in the pool drops and eventually dries out completely. Amphibians are in a race against time to metamorph before that happens.

So, as you can see, tadpoles and trees have a surprisingly close relationship. All of these compounding factors allow us to tell a lot about wood frog evolution, just by looking up.