1. Consequences of Climate Change: Temperature effects on growth rate

2. How do animals survive in cold places?
Vs.

3. 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

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

5. 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!

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

7. 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

8. Effects of climate change on insects
Expanding geographic ranges

9. Effects of climate change on insects
Faster metabolic rates

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

11. Epirrita autumnata
(Geometridae)

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

13. 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

14. 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!