The Evolution Report, hosted by Paul Wilson (paul.wilson@csun.edu)

The Evolution Report is a series of audio programs on evolutionary topics. It is primarily intended to be supplemental instruction for BIOL 322 Evolutionary Biology. Students say that they don't have enough time to study more than they are already studying, but many spend tons of down-time in their cars and relaxing before bed. Our idea then was to produce an entertaining show that could be listened to during this down-time and that would not consume high-quality time. The goal is to make evolutionary topics more familiar.  The Evolution Report is not meant to be a thing that itself can be studied. Instead, after listening to the Evolution Report we imagine that material in class will be absorbed more easily and be more interesting. We also hope that the Evolution Report will entertain and inform people not in 322 who take an interest in the origins of adaptations and the diversity of life. Funding for the Evolution Report has been provided by a grant by the NIH to Dr. Maria Elena  Zavala for supplemental instruction in the biomedical sciences, particularly so-called "gatekeeper courses", i.e., those  that students of the biomedical sciences need to do well in early during their college careers. Click here for our list of supplemental materials, and here for more on the NIH-funded minority programs at CSUN. Additional funding has been provided by a Judge Julian Beck Grant administered by CSUN. Episodes do not depend on one another. Students taking 322 might want to listen to them in the following order. Clicking on the title will open an .mp3 file of about 27 MB.  Most people have their browsers set to just play the file.  If you want to get it on your .mp3 player, you should probably right click or hold down control while clicking so as to "download link to disk", then copy over to your .mp3 player.

Selection Thinking - Dr. Jim Hogue who teaches evolutionary biology at CSUN talks about what he want 322 students to incorporate into their daily thinking (as opposed to what we can test them on).  What Dr. Hogue calls "Selection Thinking" is central to his course.  We also talk about other bits of evolutionary logic, like "Tree Thinking".

Adaptationists Program - In 1979 Gould and Lewonton offered a critique of the adaptationist's program in which they criticized people for believing the first story that came to mind about the origins of a trait.  The eventual response was an expansion of the range of interpretations of the historical origins of traits and a strengthening of how one makes  ainferencesbout adaptations.  This topic is reviewed with Dr. Rick Shine (University of Sydney), a prolific evolutionary biologist who mainly studies reptiles.

Single Locus Evolution - Dr. Polly Schffiman, who teaches 322, simplifies evolution down by considering a single genetic locus. She relates Hardy-Weinberg equilibrium  as "control conditions," and explains mutation, selection, gene flow, drift, and hitchhiking as causes of evolution. This is the foundational explanation upon which more complex evolutionary scenarios are built.

Isolating Barriers - "Speciation" is defined as the origin of reproductive isolating barriers. Dr. Dave Gray, who teaches 322 at CSUN has done extensive studies of speciation in crickets. He tells of his work in this interview, using it to illustrate many of the factors that may be involved in speciation.

Evo Devo Ginger Banana - Dr. Chelsea Specht (UC Berkeley) explains the joining of evolutionary phylogenetics with developmental genetics, particularly in plants. She works on the Zingiberales, containing bananas and gingers. She explains the a-b-c model of floral development and how the genes involved are found not only in flowering plants.

The Breeder's Equation - Dr. David Houle (Florida State University) rearranges the equation that is usually expressed as ResponseTOselection = Heritability × SelectionDifferential, changing it to ResponseTOselection = AdditiveGeneticVariance × Selection Gradient. The multivariate form of this is R = G ß, which he explains in terms of the adaptive landscape. Life history variables turn out to have a high "evolvability".

Only the Good Die Young - Dr. David Reznick (UC Riverside) explains life history evolution. A life table is a schedule of survivorship lx and fecundity mx for each age class x; these numbers are components of fitness. Using an example he has studied extensively, guppies from high predation sites have shorter lives, reproduce sooner, and store less fat than guppies from low predation sites. However, they do not meet the prediction that high predation should cause accelerated scenescence compared to low predation, invoking more complex explanations that are also rooted in the math of life tables.

Charlie's Words - My father Richard Wilson reads excerpts from On the Origin of Species (1st edition).

Inplace or Assembled
- Dr. Carlos Herrera (Estación Biológia de Doñana)  tells of the two fields of explanation for how the organisms in a community are apt to one another.  At one end of the spectrum, these organisms specifically have adapted to one another in this community; at the other end of the spectrum, they evolved in many other places under many other circumstances and were assembled in this community because they can use each other.  Examples are given concerning birds-n-fruits, pollinators-n-flowers, and bugs-n-leaves.

The Engine of Macroevolution - Dr. Richard Squires of the Geology department at CSUN gives an account of the history of life on Earth, emphasizing how plate tectonics has caused many of the great changes.  Tectonic changes result in global climate change, the rise and fall of sea levels, vicariance and exchanges, and volcanism.

Ultimate & Proximate
- Dr. Maria Elena Zavala (who also administers the grant that funds the Evolution Report) explains the complementary roles of ultimate and proximate explanations in biology. Her training in evolutionary biology still sets the stage for her scholarship in cell biology.

Powerful Species & Their Prey - Dr. Geerat Vermeij (UC Davis) tells of the evolutionary effects of predation and more generally competition. Various adaptations arise in prey and in predators. Predators have power over prey, and because losing a life is worse than losing a diner, heavy investment in defense ensues, particularly in high-energy environments. Communities are prone to escalation when both opponents can be hurt. Losers fill in the intersticies of the economy. After a crash, first quick metabolizers are favored, eventually the community becomes more complex. Top predators are drawn from other guilds, and their monopoly rarely last for long. This interview abstracts much of Vermeij's (2004) book, Nature: an Economic History.

The Uses of Trees - Dr. Kevin Omland (University of Maryland Baltimore County) explains how one uses phylogenies (especially near the species level) for ancestral state reconstruction, seeing the relative recency of common ancestors, dating divergences, studying convergent evolution, asking if two phylogenies are concordant as one would expect from cospeciation, and as a basis for circumscribing taxonomic groups.

The Meanings of Sex - Mia Adreani and Janna Fierst (former master's students) talk about how evolutionary biologists use the words 'sex' and 'sexual', and how sex is a central topic in our field, but not entirely for the reasons that first come to mind.  Sex, sexual:  (1) the systematic reorganization of the genome through meiosis and fertilization; (2) gender strategies for reproduction; (3) pertaining to relationships between the genders; (4) in certain organisms copulation, copulatory.

For Whom Selection Benefits - Dr. Leonard Nunney (UC Riverside) explains why the adaptations of individuals are not usually fashioned for the good of the species, then untangles other levels of selection, such as kin selection, selection among cells, and selection among lineages. He explains why we get so many types of cancer and why most species remain sexual.

Plants & Herbivores - Dr. Conchita Alonso explains classical views of how herbivores such as caterpillars evolve on diverse plants and how plants have evolved in face of these enemies. She addresses the adaptive nature of defensive traits, tradeoffs, and key innovations.

Mating Systems in Plants
- Dr. Steven Weller (University of California Irvine) traces the paths of evolution from one mating system to another in plants, including discussion of the evolution of selfers, gynodioecy (females + hermaphrodites), dioecy (females + males), and heterostylous species.

Changin Times in Species Exploration - Dr. Marshal Hedin (San Diego State U) explains the flood of work in molecular systematics caused by genetic tools breaking the dam behind which difficult problems have been accumulating for 300 years since Linneaus. Topics include a critique of species barcoding, detecting cryptic species, studying population genetic structure in low-dispersal groups, and unraveling the origin of cave-dwelling species. Systematics provides a biologically relevant organization for knowledge of various organisms. Good classifications, including good species concepts, are based on multiple lines of evidence.


Links to stories from public radio
Fresh Air - We remember paleontologist and evolutionary biologyist Stephen Jay Gould
Science Friday - Richard Dawkins, Pilgrimage to the Dawn of Evolution
Science Friday - Ross MacPhee, Dinosaur extinction and the rise of mammals
Science Friday - Edward O. Wilson, Bridging Science and Religion
Science Friday - Darwin exhibit makes N.Y. opening
Fresh Air - Evolutionary biologist and journalist Olivia Judson

Links to related sites
my 322 class website: www.csun.edu/~hcbio028/322.html
my home page: www.csun.edu/~hcbio028/cv.html
Dave Gray's 322 class website: www.csun.edu/~dgray/Evol322/Evolution.html
Freeman and Herron's textbook: http://wps.prenhall.com/esm_freeman_evol_3
Berkeley's Museum of Paleontology: www.ucmp.berkeley.edu
Society for the Study of Evolution: www.evolutionsociety.org
American Society of Naturalists: www.amnat.org
Darwin's writings on the web and searchable: http://darwin-online.org.uk/