Biophysical field methods online offers a practical approach to biophysical ecology, which applies physical concepts, principles and techniques to the interpretation of animal-environment interactions. These include how physical laws, such as the laws of thermodynamics, affect the abundance and distribution of animals and plants, the nature of microclimate, the ecological niche, and the integration of physiology and evolutionary ecology.
With specific ecological questions in mind, we aim to teach practical methods for reliably measuring temperature and humidity and their physical drivers in the field. Temperature and humidity are commonly reported in field studies, but they are usually measured with little attention to the physical principles that make the measurements meaningful and reliable. Without such attention, the results can be worse than meaningless: they can be misleading.The course is composed of seven lessons, each subdivided into several sections. The first third of the course deals with the physics of heat: energy, temperature, the differences between them and how biological systems are constrained by the laws of thermodynamics. Next the course delves into the physics of water, its colligative properties, and the energetics of phase changes from ice to liquid water and liquid water to water vapor. Then, the course focuses on the physics of water potential. All these concepts are tied together through their common currency—energy—and are demonstrated with several examples of how these concepts properly applied can lead to a deeper understanding of the organism and its environment.
Temperature and heat. After viewing this lecture you should know the difference between temperature and heat and how they are related.
After reading "Scientific writing instructions" you should have a good idea of the level of writing that will be required of you.
The three fundamental laws of thermodynamics made simple
Temperature scales, Fahrenheit, Celsius and thermodynamic (absolute). How temperature scale endpoints came about.
How to explicitly associate temperature to heat through knowledge of the specific heat of a material and thermal capacitance of an object.
Latent heat of vaporization and what happens when water changes from liquid to gas and vice versa.
Definition of the operative temperature and how it relates to the first law of thermodynamics. Also, the mechanisms of heat transfer between animals and their physical environment and the energy balance equation.
Energy lifestyles --Here you will learn about ectothermic animals as energy misers and endothermic animals as energy wastrels andhow the body temperatures and energy budgets of the two groups differ because of their different lifestyles. The effects of body size on energy use are also discussed.
In this section, modes of heat exchange are discussed and by its end you will have learned about heat exchange through radiation, convection and conduction.
We will now go the next step and in this lesson you will learn to measure the operative temperature on "animals" of different sizes and colors. You will learn how the operative temperature is affected by radiation and convection and why small animals are coupled to convection, whereas large ones are radiation-coupled.
In this section we'll will teach you about the effects of body size, shape and color on the operative temperature. You will learn a simple way for estimating surface area of animals and then learn to write an energy balance equation, taking into account convection and solving for radiation. The result will be an equation for the operative temperature Te.You will learn in some depth about the relationships and importance of volume and surface area and the terms radiation- and convection coupled.
This lesson will take you from models of animals studied und quite controlled conditions to learning how to measure operative temperatures under field conditions, where there are a wide variety of microclimates that an animal can occupy in a given habitat. You will also learn the utility of measuring the operative temperature of an animal (or plant). But before you can go out and measure these variables, you will learn how to calibrate your measuring devices. You will see three demonstrations of how microclimates can be used by animals and plants to their own ends.
Here you will learn how to explain the daily pattern of behavior of an ectothermic animal by following its operative temperature.
Water has what are called colligative properties. These, the reduction of freezing point, the elevation of boiling point, the reduction of vapor pressure, and osmotic pressure, all depend on the concentration of solute molecules (or dissociated ions) in solution. In this section you will learn about these properties and their relationships with the environments in which animals and plants live.
This section will introduce you to water vapor in the air and its relations with water in the liquid phase. You will learn how to correctly describe water in these two phases and the basic physical principles of evaporation and condensation.
Here you will learn about the relationship between temperature and relative humidity and how relative humidity is a misleading measure. You will also learn about the use of a specialized iButton data logger called a Hygrochron to follow absolute and relative humidity over a 24 hour period.
This section deals with water potential in soils. You will learn how water actually moves through soils as a function of the interactions between the different forms of water potential.
In this part you will learn about the association between water potential and relative humidity and that water potential is the capacity to do work. Finally, you will learn about the water potential of air, what the measure of relative humidity is good for, and how water moves up in tall trees.
In this section you will first review what you have learned about relative humidity then how to make molds of animals whose evaporative water loss you wish to study. That will lead you to the next section where you will learn to use the molds evaluate evaporation in several microhabitats.
Here you will learn to measure water potential in the soil around a termite mound with a gypsum sensor and how to analyze these data using those from a previous project.
Based on the method learned in section 7.3., you will learn to analyze soil water potentials around a termite mound using data collected a few years ago when these mounds were being extensively studied. You will also learn what termite mounds are all about.
I am a Professor of Biology at the State University of New York College of Environmental Science and Forestry in Syracuse, New York.
I am a physiologist by training but with a deep interest in the interface of physiology, ecology, adaptation and evolution. You can read some of my thoughts in two books I have published: The Extended Organism: The Physiology of Animal-Built Structures (2007) and The Tinkerer's Accomplice: How Design Emerges from Life Itself (2007), both published by Harvard University Press. I have completed a third book, Purpose and Desire: Biology's Second Law, which I hope will be published soon.
My current research focuses on the problem of emergent physiology in social insect colonies. specifically the mound building termites of southern Africa.
I am a physiological ecologist and am interested in energy
and water exchange between animals and the environment and in the physiology of
thermoregulation and osmoregulation in desert animals - especially birds, bats
and rodents. I was trained in zoology at Tel Aviv University and did my Ph.D.
at Duke University and in Antarctica on the energy use of emperor penguins. My
post-doc was in biophysical ecology at the University of Wisconsin, Madison. More
recently, I have been studying Burrow architecture: Namely, how are burrows
"designed", through natural selection on their builders to suit the
builder's physiological needs, thus becoming become part of the organisms
"extended physiology". More at http://in.bgu.ac.il/en/bidr/SIDEER/MDDE/Pages/staff/berry-pinshow.aspx.