The environment The environment is a complex of factors which act on an organism or a group of organisms The environmental factors are usually divided into abiotic factors and biotic factors.

Biotic Factors Number and kinds of organisms Plants Animals Decomposers

Biotic Factors Comprise the interrelationships between living organisms Interspecific Intraspecific

Biomes: Temperature and moisture dependence (Ricklefs 2001)

Abiotic Factors Available light Water Soil nutrients Temperature

Temperature Regulation and Adaptation   I. Introduction A. Reasons for regulating temperature II. Basic heat balance equation A. The components B. The equation Terms: homeotherms, endotherms, poikilotherms, ectotherms III. Adaptations for temperature regulation and tolerance A. Regulating – manipulating the heat balance equation B. Avoiding – dormant stages 

II. Organism adaptations and tolerance  Terms: Adaptation, fitness, tradeoffs, genotype, phenotype, ecotype, plasticity, homeostasis, feedbacks A. Adaptation B. Homeostasis C. Law of Tolerance, acclimatization

Adaptation Any heritable behavioral, morphological or physiological trait that maintains or increases the fitness of an organism under a given set of environmental conditions.

How have these animals adapted to their environment? Adaptation How have these animals adapted to their environment?

Camel Has long legs to keep body away from hot sand Can store fat in hump. Can go for long periods without water.

Camel Can close nostrils to keep out sand. Has long eyelashes to keep out sand. Many blood vessels just under the skin to cool the blood.

Polar Bear Has white fur for camouflage. Each hair is hollow for extra insulation. Has sharp teeth and claws to catch and eat prey. Has ridged foot pads to prevent slipping.

Penguin Has thick layer of fat to keep warm. Produces oil to keep feathers waterproof. Stream lined body for swimming.

Golden Eagle Large wing span for gliding. Sharp talons for catching and holding prey. Hooked beak for tearing meat. Large eyes for spotting prey from great distances.

Shark Stream lined body for swimming. Fins to propel through the water. Sharp teeth. Gills to breath under water.

Ostrich Long legs to run fast. Large eyes to see long distances. Long feathers to provide more shade to eggs and to keep body warm at night.

Homeostasis Negative feedbacks Positive feedbacks

Law of Tolerance

Acclimation and adaptation

Acclimation is a reversible change in structure. Acclimation is a shift in the range of physiological tolerances of the individual. Some examples: growing thicker fur in winter producing smaller leaves in the dry season increasing the number of red blood cells at higher elevations producing enzymes with different temperature optima producing lipids that remain fluid at different temperatures (c) 2001 by W.H. Freeman and Company

Tolerance – effects of environmental change? Chuckwalla, Valley of Fire http://www.richard-seaman.com/Reptiles/Usa/Nevada/ValleyOfFire/

Temperature regulating behaviors in lizards

I. Introduction Reasons for regulating temperature Metabolic limits, enzyme kinetics Behavioral consequences 1

Q10 Q10 = T

A. Introduction Note acclimation 1

Behavioral consequences - animals

Behavioral consequences - plants Adaptation or acclimation? Compare with acclimation

Terms Homeotherms Endotherms Poikilotherms Ectotherms Heterotherms

Subphylum: Vertebrata Group: Gnathostomata Kingdom: Animalia Subkingdom: Metazoa Phylum: Chordata Subphylum: Vertebrata Group: Gnathostomata Superclass: Pisces (Fishes) Superclass: Tetrapoda Class: Osteichthyes Class: Amphibia Class: Reptilia Class: Aves Class: Mammalia

II. The heat balance equation A. The components Or gain (Hir) Loss only! (Unless including condensation)

Body size and basal metabolic rate

Bergmann's Rule asserts that It's also a matter of basic physics that the larger a sphere, the less is its surface area relative to its total volume. Therefore, large balls lose heat more slowly, relative to their size, than small ones. You might guess, then, that animals tend to be larger in cold areas than in tropical ones. In fact, Bergmann's Rule asserts that geographic races of a species possessing smaller body size are found in the warmer parts of the range, and races of larger body size in cooler parts.

ALLEN'S RULE In fact, in ecology there's a "rule" recognizing this principle at work among geographical races of single species. Called Allen's Rule, it states that certain extremities of animals are relatively shorter in the cooler parts of a species' range than in the warmer parts. By "extremities" is mainly meant arms, legs, ears, and snout or nose.

Basal metabolic rate – endos & ectos

B. The equation

Temp balance for a mussel – constant conditions

Temp balance for a mussel – variable conditions

III. Adaptations for regulation & tolerance Regulation – manipulating components of the energy balance equation. 1. Adaptations & acclimations 2. Similarities and differences among plants, endos & ectos.

Similarities – radiation, coloration Clear-winged grasshopper Encelia farinosa – desert brittlebush http://www.botgard.ucla.edu/html/botanytextbooks/generalbotany/shootfeatures/generalstructure/leafcolor/a0893tx.html

Developmental Responses in Grasshoppers The grasshopper Gastrimargus africanus can match its color to that of its surroundings: helps avoid detection by predators epidermal pigments laid down at each molt respond to hormones produced in the brain in response to quality and intensity of light: animals are green in rainy season as dry season comes on, animals are brown following fires, animals are black (c) 2001 by W.H. Freeman and Company

What about the arctic fox? Winter coloration Summer coloration http://www.biosbcc.net/ocean/marinesci/04benthon/arclife.htm

Radiation: Orientation

Evaporative cooling http://www.kateconnick.com/postcards/bcpant.jpg http://www.css.cornell.edu/faculty/hmv1/watrshed/Etrans.htm http://www.ci.ann-arbor.mi.us/SafetyServices/EmergencyManagement/EMD/heatwave.html http://www.kateconnick.com/postcards/bcpant.jpg

Morphology/growth form: conduction & convection Black-tailed jackrabbit http://homestudy.ihea.com/wildlifeID/043jackrabbit.htm

Fig. 4.17 (4th) Fig. 5.19 (5th)

Metabolic heat

Differences Does the prevalence of some mechanisms differ among plants, endotherms, and ectotherms? Which ones? Why?

B. Avoidance Dormancy – plants (seeds, cold tolerance) Burrowing, torpor, hibernation & estivation - animals

Summary Range shifts often tied to temperature extremes. We can understand components of heat balance individually. Adaptations for heat gain/loss: understand in the context of individual components of heat balance equation.