Consequences of Climate Change: Temperature effects on growth rate

How do animals survive in cold places? Vs.

Endotherms vs. Ectotherms Metabolic rate: The sum of energy flowing through an organism over given period of time Endotherms: organisms that internally regulate their body temperatures to sustain metabolism. EX: mammals Ectotherms: organisms that do not internally regulate body temperatures (body temp = outside temp) EX: insects, reptiles

Ectotherms and temperature Chemical reactions occur faster at warmer temperatures Ectotherms maintain a faster metabolism at warmer temperatures (until temps reach the thermal optimum)

Climate change in the Arctic Rapid environmental change is occurring in the Arctic Temperatures are increasing at 2X the rate of the rest of the globe!

Climate change in the Arctic This has consequences for aquatic and terrestrial plants and animals

Effects of climate change on insects Reduced mortality Southern pine beetles can now survive in NJ and Long island because minimum winter temperatures are increasing

Effects of climate change on insects Expanding geographic ranges

Effects of climate change on insects Faster metabolic rates

Caterpillars in the Arctic Some experience population outbreaks May be part of the reason the Vikings left Greenland! Video link

Epirrita autumnata (Geometridae)

Our question: How will temperature affect caterpillar growth rate? Mass (g)

Our question: How will temperature affect caterpillar growth rate? Methods Caterpillars collected from shrubs in Greenland and reared at two temperatures Measured mass 4 times over 6 days 10 C 18 C

How temperature will affect caterpillar growth rate? Draw two curves, each representing a temperature treatment 10 C 18 C Date Mass (mg) Now…let’s look at the data!