1. Physiological Ecology How animals cope with environmental change, and what it means to their distribution and abundance in nature Steve McCormick USGS, Conte Anadromous Fish Research Center and Dept. of Biology, Dept. of Environmental Conservation, UMASS

2. What environmental factors are important to animals? ? AbioticBiotic Food Predators Disease Conspecifics

3. How do animals respond to environmental change? Overall strategies for coping: conform or regulate Homeostasis: maintaining a constant internal state in the face of environmental change.

4. How do animals respond to environmental change? Overall strategies for coping: conform or regulate Example: Changes in external salinity. External osmotic pressure (mOsm) SharksTeleost fish

5. How do animals respond to environmental change? Overall strategies for coping: conform or regulate No internal heat generation. Internal heat generation. Constant body temperature. Variable body temperature.

6. How do animals respond to temperature change? Make Believe 101: You’re a fish. How do you respond to increased temperature? Hint: oxygen uptake increases. Fast Slow

7. Physiological Adaptations to Temperature Production of enzyme isoforms with different temperature optima. Trout acclimated to cold water make a different acetylcholinesterase than trout acclimated to warm water. Abundance of many enzymes will also change.

8. Physiological Adaptations to Temperature Homeoviscous adaptation Maintaining a constant membrane fluidity (“liquid crystal state”) is essential to normal function of cells. Temperature strongly influences the fluidity of membranes. Animals increase the ratio of saturated:unfaturated fatty acids in cell membranes in response to increased temperature increase in order to maintain membrane fluidity.

9. Physiological Response HYPO- THALAMUS ENDOCRINE GLAND Target Tissue HORMONE (IN BLOOD) Environmental change Homeostatic disturbance RELEASING HORMONE [HORMONE BINDING PROTEIN] HORMONE RECEPTOR NEGATIVE FEEDBACK Target Tissue Hormones and Acclimation Provides sensing of enviornment or internal disturbance highly specific signalling coordination among tissues feedback system

10. Temperature and Acclimation Effects on Performance What are the possible outcomes of acclimation? How would the shape of this curve change after acclimation to high temperature? What are some examples of organismal performance?

11. How do animals respond to environmental change? Acclimation (often) results in a greater capacity near the acclimation temperature. - but there are usually trade-offs Survival has the widest capacities. Activity, growth, and reproduction are usually more constrained. No universal pattern of life history sensitivity to temperature. (Fry and Hochachka, 1970)

12. 12 Tolerance of temperature change varies among species Differences in tolerance polygons reflect diversity in thermal capacities Antarctic Rock Perch (5) Salmon (4) Goldfish (1)

13. Most animals have thermal preferences For example, most fish will precisely select position in a thermal gradient The “fundamental niche” (determined by physiological ability) may be different from the “realized niche” (what occurs in nature). The latter may be driven by behavior and ecological constraints such as presence of predators and prey.

14. Metabolism = Energy Utilization I = E + M + G I = ingested energy E = excreted energy M = metabolic energy G = growth M s = standard metabolism M f = feeding metabolism M a = active metabolism

15. Fate of a 100 calorie in fish I = E + M + G

16. There is an energetic cost to food processing and growth Specific dynamic action (SDA) is a postprandial (after feeding) elevation in metabolic rate

17. Factors Influencing Metabolic Rate Metabolic rate increases with size… but weight specific metabolic rate decreases with size. - among and within species. There is a substantial cost to the endothermic strategy.

19. M O2 = rate of O2 consumption Q = cardiac output Ca O2 = arterial oxygen content Cv O2 = venous oxygen content f H = heart rate V s = stroke volume

20. Class exercise Can animals adapt (evolve) in response to climate change? What are the physiological mechanism involved? How will their capacity to adapt affect their geographic distribution? Pick one example of climate change impacts, such as temperature, rainfall, sea level, ocean acidification, etc. You can choose one or several papers to bolster your arguments, but an exhaustive literature review is not necessary.