Although people have been altering earth's landscapes to some extent for tens of thousands of years, humankind today is causing massive changes to the planet. Such widespread environmental change is accompanied by accelerating rates of species extinction.
Herman H. (Hank) Shugart W.W. Corcoran Professor of Environmental Sciences & Director, Center for Regional Environmental Studies
Regions of Interest: Global
Research: Global change, systems ecology, systems analysis and modeling, forest ecosystem analysis and dynamics, ornithology.
Hank Shugart is a Highly Cited™ Scientist and 2006 University of Virginia Distinguished Scientist.
Hank is a systems ecologist whose primary research interests focus on the simulation modeling of forest ecosystems. He has developed and tested models of biogeochemical cycles, energy flow and secondary succession. In his most recent work, he uses computer models to simulate the growth, birth and death of each tree on small forest plots. The simulations describe changes in forest structure and composition over time, in response to both internal and external sources of perturbation. The models are applied at spatial scales ranging in size from small forest gaps to entire landscapes and at temporal scales of years to millennia.
Abstract: Herman H. ("Hank") Shugart, Jr. is the W.W. Corcoran Professor of Environmental Sciences and the Director of the Center for Regional Environmental Studies at the University of Virginia. He received his Ph.D. in Zoology from the University of Georgia in 1971, and worked for the next 13 years in Tennessee -- eventually as a Senior Research Scientist at Oak Ridge National Laboratory and as a Professor in Botany and the Graduate Program in Ecology at the University of Tennessee. In 1984, he moved to his current position at University of Virginia. Dr. Shugart has also served as a Visiting Fellow in the Australian National University (1978-1979, 1993-1994), in Australia's Commonwealth Industrial and Scientific Research Organization, Division of Land Use Research (1982) and Division of Wildlife and Ecology (1993-1994), in the International Meteorological Institute at the University of Stockholm, Sweden (1984), and in the International Institute of Applied Systems Analysis, Laxenburg, Austria (1987,1989). He has served on the editorial board of several scholarly journals including Ecology and Ecological Monographs, Annual Reviews in Ecology and Systematics, Biological Conservation, Landscape Ecology, Journal of Vegetation Science, Forest Science, Global Change Biology and The Australian Journal of Botany. He is the author of more than 300 publications including 11 books, 60 book chapters and 90 papers in peer-reviewed journals.
I love books that dive just that little bit deeper into a topic than usual. Examples that come to mind are: "Guns, Germs and Steel" and "Collapse" (Jared Diamond), "1491" (Charles C. Mann), and "The Worst Hard Time" (Timothy Egan).
"How the Earthquake Bird Got its Name" delves into the complexities of environmental change by exploring the successes (and failures) of selected animal populations.
While a variety of "stresses" are explored (earthquakes, fires), this book shows very clearly the extraordinary effect that humans have had on the environment.
Shugart debunks the idea of a "balance of nature" and explains how fragile environmental "equilibrium" can be.
If you'd like to have a better understanding of the effects of human civilization on the environment - from a scientific point of view - this is a terrific resource.
Clear, interesting essays illustrating concepts of ecology, each starting from an historic observation of some particular animal or plant. While not 'fables,' as the title might suggest, the accounts are directed to a general reader and focus on the dynamic, even unstable condition of most of earth's habitats and ecosystems.
Introduction - Change is an essential part of nature
Ivory Billed Woodpecker - A pair needs 50 square miles of territory as it picks beetles from old snags. The snags only appear 200-400 years after the tree sprouts. - Forest change processes include the formation of gaps, tiger bush and fir waves. - A mature forest should have patches with all stages of the gap replacement cycle.
Penguin - The name penguin comes from Welsh and means white head, a reference to an island off Newfoundland. The southern penguin was named after the similar great auk which was called the penguin at that time. - Joseph Grinnel defined the ecological niche as the set of attributes that allow an organism to fir into the environment. - Convergence (auk and penguin) is the result of two animals adapting to the same niche. - Gause's principle, or the competitive exclusion principle: no two species can occupy the same niche.
Packrat - Packrats collect material into middens and urinate on them. The urine forms amberite, preserving the midden. Middens thousands of years old allow past vegetative patterns to be known. - A 24,000 year reconstruction near the Grand Canyon shows that before the last ice age, the vegetation was much different than today. - During warming and cooling periods, the vegetation does not just rise up and descend down through elevation. Instead the niches appear to change, resulting in new vegetative zones. - Milankovitch cycles: 105,000 year cycle in the degree of roundness of the elliptical orbit of the earth around the sun; a 41,000 year wobble in the axis of spin of the earth; a 21,000 year cycle determined by whether the water filled southern hemisphere or the more terrestrial northern hemisphere is closer to the sun. - Pollen analysis shows that past forests have mixtures of trees different from today's forest - more Alder, for example. - Megafaunal extinctions have occurred in many places on earth when man arrived. - These extinctions may not have occurred because man hunted the large animals, but because he changed the environment.
Red Billed Quelea - This is an African weaver finch found in grasslands. It is a seed eater that has very successfully adapted to seasonal and shifting supplies of seeds. It is a great pest of crops grown in Africa. Population estimates are to 10 billion. - Birds will adapt to localized food supplies. Irruptive migration is ad-hoc while regular or obligate migration is known in many species. Route finding techniques include internal clocks, compasses and maps. Zugenruhe which is restlessness at night, preparatory to migration. Migration habits can evolve over short time frames. - The Passenger Pigeon was adapted to eating the seeds of the AAAAmerican Beech and Oak. As they produce seeds only over wide intervals, the p. pigeon had evolved huge irruptive migrations. As they moved in very large numbers, they would cause massive disturbances to the forests.
Beaver - The beaver makes major changes to the environment, and were once more common than today. - Keystone species are those on which other animals of the ecosystem depend upon. An example are the honeyeaters of Western Austrialia which depend on one species of Banksia that blooms and sustains the honeyeaters through a season that has no other nectar producers.
Moa - The Moas of New Zealand disappeared between the arrival of the Maori and the arrival of the Europeans. They appear to have been creatures of the forest and shrubland. Their disappearance seems to have been due to a combination of extensive forest clearing and burning, direct predation and introduced organisms such as rats and dogs. - As well as 11 species of Moa, another 21 species of large ground birds disappeared. - The extinction of species with the arrival of man is a common pattern. - The dynamics of islands near to mainland are driven by colonization. - The dynamics of distant islands, such as Hawaii and the Galapagos, are driven be speciation. Organisms tend to lose specializations that are no longer needed competitively. Large species become small (nanism) and small species become large (gigantism). Species diversify to fill empty niches. - Island species are particularly vulnerable to environmental change. About 80% of animal species known to have become extinct have been island animals.
The Wolf That Was Woman's Best Friend - The chapter title refers to the surprising practice of native peoples to suckle young animals, such as dogs. - The dingo arrived in Australia about 4000 years ago - well before man (40,000 years ago), probably with sea faring Polynesians as a food item. It never got to Tasmania. It's arrival coincides with the disappearance of the Tasmanian wolf and devil from Australia. - A review of the domestication of a relatively few species of animal by man. Domestication resulted in major changes to landscapes.
Rabbits - Rabbits were originally African, with some confined to the Iberian peninsula. - They were domesticated by French monks between 500 AD and 1000 AD. - They have been introduced in many countries with Australia being a notable example. - The introduction of exotic species results in a reduction of native species. In New Zealand, the result was an increase in the number of species. - Overall the introduction of exotics reduces the world diversity. If the world were one common landscape, the number of mammals would be one have of the current total. - Rabbits have been controlled in Australia to some degree by the introduction of diseases such as Myxoma and rabbit hemorrhagic disease. - A new approach of virus vectored immunocontraception (VVI) is being developed whereby a disease is genetically modified to leave the animals sterile.
Planetary Stewardship - It is up to man to assume stewardship of the earth.