Robert Sokal: Statistical giant in ecologists' boots

Robert Sokal (1960):
from Wikipedia

No student of my generation, trained in ecology and evolutionary biology, will not have heard of Sokal and Rholf’s Biometry textbook. Most would have used it in a class or to inform their analyses. Sadly, Robert Sokal passed away last month at the age of 86. He had a tremendous career, mostly at Stony Brook University in New York, and contributing to statistics and science for over half a century. As a testament to his impact, the third edition of Biometry has been cited over 14000 times! It is the canon for experimental design and analysis in the biological sciences.

He had extraordinary and tumultuous experiences as a youth -fleeing Nazi Germany and being raised in China. Whether, such experiences give rise to greatness, or whether his innate intellectual abilities sealed his destiny is an interesting question. Regardless, his impact and legacy will be deservedly long lasting.

Ross Crozier, evolutionary biologist and conservation biologist

Sadly, one of Australia's leading evolutionary biologists, Ross Crozier passed away suddenly last week (Nov. 12th, 2009). As a Professor at James Cook University, he worked on a plethora of evolutionary issues, from understanding the evolution of sociality in insects to population genetics and molecular phylogenetics. To my mind, his most influential papers were on how we can use patterns of evolutionary history in guiding conservation decisions -the agony of choice. While he promoted the conservation of phylogenetic diversity, per se, his great insight was that even comparing species that are relatively divergent does not mean that they are equally valuable, and we should consider information content as well. That is, a species with 80,000 genes is more valuable than a species with 20,000 genes, since the 80K-gene species has greater information content.

"Differences in the information content of genomes led to the realization that, other things being equal, some organisms have intrinsically higher conservation worth than others." -Ross Crozier

Ross also recently was the handling editor, at Ecology Letters, on a paper of mine and his insights and support were greatly appreciated and helped to improve our manuscript in numerous ways.

Here are my two favorite papers of his.

Crozier, R. H. 1992. GENETIC DIVERSITY AND THE AGONY OF CHOICE. Biological Conservation 61:11-15.

Crozier, R. H. 1997. Preserving the information content of species: Genetic diversity, phylogeny, and conservation worth. Annual Review of Ecology and Systematics 28:243-268.

Researcher spotlight: Tadashi Fukami

Increasingly, ecological explanations for extant community patterns are relying on dynamics operating across multiple spatial and temporal scales, linking small and large scales, and the here and now with evolutionary history. The traditional boundaries of sub-disciplines are blurring. I think that few other young scientists straddle these boundaries as successfully as Tad Fukami, and new assistant professor in the Department of Biology at Stanford University. Tad uses a broad array of theoretical and experimental approaches to understand how ecological communities are put together. From laboratory microcosms to rat-infested islands, and from the computer to remote locations, he is able to pull together disparate pieces of information into a central narrative about the assembly of communities.

I asked him why the question of community assembly interested him so much, and he gives much credit to his advisors, Jim Drake (also my PhD advisor) and Dan Simberloff both in the Department of Ecology and Evolutionary Biology at the University of Tennessee. But more than this, he says that:

“you need to look into the historical background of species interactions to understand the apparently inexplicable variation in the way species interact and the way communities are structured by the interactions.”

and certain aspects of this research obviously excite him. He goes on to say:

“One particularly intriguing thing is the great effect that small chance events that cause variation in early immigration history can have on long-term community development.”

Most ecologists gain their expertise by coming to understand and appreciate the details and intricacy of particular organisms or ecosystems. But Tad is especially noted for his use of an amazingly broad assemblage of systems and methods. I asked him why he used so many different systems, and how he chose those to test his ideas. He said that his work has benefitted from many exciting collaborations and that he has:

“been very lucky to meet many great people who have expertise on specific organisms and systems that a person with diffuse interests like me doesn't have.”

But I think that there may be something deeper and more reassuring. That is, the fact that one could study a multitude of systems, testing the basic dynamics of community assembly, means that there are regularities in how communities are assembled. That you can study stochastic historical events in bacterial microcosms and inform your understanding of plant succession means that while we individually take on these, at times, daunting research projects, our collective understanding of ecological processes are threaded together in a great fabric. And no one is a microcosm of this more than Tad Fukami.

Key recent papers

Fukami, T., Beaumont, H. J. E., Zhang, X.-X. & Rainey, P. B. (2007) Immigration history controls diversification in experimental adaptive radiation. Nature 446: 436-439.

Fukami, T., Wardle, D. A., Bellingham, P. J., Mulder, C. P. H., Towns, D. R., Yeates, G. W., Bonner, K. I., Durrett, M. S., Grant-Hoffman, M. N. & Williamson, W. M. (2006) Above- and below-ground impacts of introduced predators in seabird-dominated island ecosystems. Ecology Letters 9: 1299-1307.

Fukami, T., Bezemer, T. M., Mortimer, S. R. & Van der Putten, W. H. (2005) Species divergence and trait convergence in experimental plant community assembly. Ecology Letters 8: 1283-1290.