1	Adaptation Traits that function to increase survival or reproduction and are due to genes (i.e., are heritable) are called adaptations.
2	Reading The reading for today’s lecture is from chapter 41, namely p. 934 – 945. Animal form and function are the product of many years of evolution, and are often considered in the evolution section of books. Adaptations are explained by stories.
3	Questions How are Oryx able to live in the desert where most animals can’t? How can the variety of fish mouths be explained? How do organisms hide? How does function change with size? And many others.
4	Understanding adaptation For each question one can do studies from which one learns something about function. This information about ‘mechanisms’ is woven into a story that explains how the organism functions. Metabolic water offers an explanation of how an organism can survive in desert (=without drinking water).
5	Adaptation vs Acclimatization Changes that increase function of an individual (such as exercise), but can not be transmitted to offspring are called acclimatization. Adaptation is reserved for increases in function that are the result of genetic change of the population.
6	Adaptation as process Biologists call the processes of becoming adapted adaptation, so the word can be a verb or a noun. Though adaptation requires changes in genes, the stage of the process where the genes are polymorphic is rarely observed.
7	Structure and Function Consider the mouth of a fish. The mouth performs functions that are part of breathing and prey capture and perhaps other activities. The ‘best’ arrangement for breathing may not be the ‘best’ for capturing quick prey, the conflict among functions results in a ‘trade-off’.
8	Ways fish feed Suction is an important component of feeding of most fish. The mouth cavity expands and water rushes in. Only a few fish use teeth to capture prey Filtering small organisms from water works for some fish
9	Alligator Gar uses its teeth
10	Largemouth bass use suction and ‘swimming over’ prey
11	Paddlefish, a filter feeder
12	Parrotfish have jaws strong enough to eat coral
13	Seahorse mouth is a narrow tube
14	Camouflage
15	Camouflage
16	Camouflage and lack thereof, Biston
17	Area and Volume The size of organisms and cells plays a big role in how they function. Volume increases proportional to the cube of length, i.e., l³. Surface area increases proportional to square of length, i.e., l². As cells get bigger it is harder to get the materials the cytoplasm needs thru the cell membrane.
18	Increasing surface area Large individuals have a variety of ways to increase the surface area in tissues and organs. Flattening Folding Branching All organs of the body have some features to increase rates of exchange of material across membranes.
19	Allometry Situations where changes in structures are NOT EXACTLY proportional to body size are described as allometric. In mammals the mass of the skeleton increases slightly faster than the increase in body mass. Dogs have bigger hearts than cats of same body mass.
20	Efficiency is not always increased by evolution Salamanders and other ‘cold blooded’ organisms are more efficient in converting the food they eat into biomass than are the ‘warm blooded’ birds and mammals, yet amphibians and reptiles have largely been replaced by mammals and birds in most ecosystems.
21	Mammals vs amphibians Mammals use a much smaller percent of the energy that they gather for reproduction and growth, but because they can gather more food per gram of mass (and perhaps for other reasons) mammal populations can grow faster than amphibians.
22	Vocabulary Adaptation Form and function Acclimatization Polymorphic Trade-off Suction Diffusion Allometry Efficiency