Ran Nathan on the Growing Importance of Movement Ecology
Scientist Interview: October 2010
Although the idea to develop "movement ecology" as a new research field unifying studies of movements of all kinds and all organisms was there eight years ago, it took several years, and many raised eyebrows of my peers, to advance this plan. In 2003, I moved to the Hebrew University, where I soon realized the wonderful opportunities to develop a new initiative of this kind in the Institute for Advanced Studies in Jerusalem.
In the 2006/2007 academic year, this institute sponsored a year-long project with Wayne Getz, Eloy Revilla, Marcel Holyoak, Ronen Kadmon, David Saltz, and Peter Smouse as wonderful core partners and perhaps 30 other associate members from all over the world. That was the best academic endeavor I have ever undertaken.
The 2008 Special Feature I edited for PNAS reports the main products of this project, calling for establishing a new paradigm for unifying movement research, proposing a general framework to facilitate this integration, and illustrating its application for a variety of taxa and systems.
How has this work been received by your peers thus far?
Well, I now rarely see raised eyebrows but rather excitement and strong support from hundreds if not thousands colleagues. The papers of this Special Feature, especially the one introducing the main concepts, are cited very nicely.
You can search the web and see how many people now define movement ecology as their main field of research, how many conferences have movement ecology symposia and sessions, how some journals now include movement ecology sections, and most importantly, that there are more and more attempts to unify movement research and seek for a general theory. This was, and still is, the declared long-term goal of this movement ecology initiative.
Are there any projects you have forthcoming that you are free to discuss?
Several of our projects on seed dispersal (by Ana Trakhtenbrot) and gene flow (by Ofer Steinitz) of Aleppo pine have recently been completed. Ana has worked with Gaby Katul to apply atmospheric models, modified to incorporate the effects of heterogeneous landscapes and topography on wind dispersal.
Relaxing the common assumption of dispersal in homogenous and flat landscapes, Ana found that the median dispersal distance and LDD generally increase, but in some cases seeds can even move against the direction of the regional wind. Ofer has shown very rapid genetic homogenization in which the few remaining native Aleppo pine populations in Israel have become genetically similar to the nearby pine plantations within only a few decades.
"Seed dispersal is important to biodiversity conservation because it plays a major role in all the main processes currently threatening global biodiversity."
In another recently completed project, Nir Sapir found that the heart rate of migrating bee-eaters during soaring-gliding flights is not significantly higher than during long rests, suggesting that this flight mode is very cheap energetically for these beautiful birds. He also found evidence suggesting that these birds may sense the change in synoptic systems associated with favorable soaring conditions 2-3 days ahead.
We also have very exciting, and I would say even ground-breaking, fresh results from the two other studies of Nir Horvitz on migration of soaring birds and Asaf Tsoar on navigation Egyptian Fruit Bats. I apologize but I cannot provide details on these projects now because of pre-publication restrictions. Hopefully, we will soon publish the first manuscripts from these exciting studies.
Other ongoing projects in my laboratory include studies of foraging in vultures (by Orr Spiegel and Roi Harel) and cranes (by Itai Shanni and Sasha Pekarsky), navigation in stone curlews (by Yotam Orchan) and pollen flow in burned Aleppo pine forests (by David Shohami), for which we have very interesting preliminary results, but it might take some time until we complete these studies and publish these results.
And, finally, I can share fresh exciting news received today on a preliminary approval of a big project with Martin Wikelski and other German, Spanish, Polish, and Israeli colleagues to investigate the lifetime tracks of white storks.
In what directions do you see your field (or key aspects thereof) going in the next decade?
We are benefitting today from the tremendous progress in tracking and bio-logging technologies, now enabling us to get more accurate higher-resolution data of smaller free-ranging organisms over larger scales and extended periods than before. Furthermore, we now have tools such as three-dimensional accelerometers and various models to assess behavior, physiological state, and external environmental conditions of the tracked animals.
Only a few years ago, movement data were sparse and of low quality, with hardly any additional information available. Another important recent trend is the tendency to go beyond specific disciplines and seek for trans-disciplinary projects. These powerful processes are going to revolutionize our understanding of movement phenomena because they allow us to address key questions that we were not able to examine before.
Yet, we will probably first need to delve into the challenges of data gathering, processing, and analysis, because the wealth of data is rapidly becoming a challenging issue itself. I thus foresee a focus on methodological developments in the next five years or so, and, in parallel, more and more insights into the causes, consequences, patterns, and mechanisms of various movement phenomena.
These should pave the road for the development of a general theory of organismal movement; hopefully movement ecology has already entered a mode of perpetual motion and advancement, so we shall see serious accomplishments at this front already during this decade.
Professor Ran Nathan
Movement Ecology Lab
Department of Ecology, Evolution and Behavior
The Alexander Silberman Institute of Life Sciences
The Hebrew University of Jerusalem
Edmond J. Safra Campus, Givat Ram
Jerusalem, Israel
RAN NATHAN'S MOST CURRENT MOST-CITED PAPER IN ESSENTIAL SCIENCE INDICATORS:
Nathan R, Muller-Landau HC, "Spatial patterns of seed dispersal, their determinants and consequences for recruitment," Trend. Ecol. Evolut. 15(7): 278-85, July 2000 with 414 cites. Source: Essential Science Indicators from Thomson Reuters.
KEYWORDS: SEED DISPERSAL, SPATIAL PATTERNS, BIRD MIGRATION, ANIMAL FORAGING, NAVIGATION, MODELING, FIELDWORK, PLANT DYNAMICS, WIND DISPERSAL, LONG-DISTANCE DISPERSAL, ATMOSPHERIC MODEL, UPDRAFTS, BIODIVERSITY, CONSERVATION, LAND USE, HABITAT LOSS, FRAGMENTATION, INVASIVE SPECIES, CLIMATE CHANGE, GENETICALLY MODIFIED ORGANISMS, MOVEMENT ECOLOGY, GENE FLOW, ALEPPO PINE.