Implications for Conservation Planners

A large and vibrant community of conservationists, scientists, politicians, and laypeople are actively engaged in intensive efforts to preserve biodiversity. One of the most important such efforts is habitat preservation. Yet even the most Herculean of efforts will save only patches of habitat in a sea of agricultural fields and spreading human landscapes. As long as humanity rules, it is doubtful that hundreds of thousands of miles of unfenced, unimpeded native habitat will be available to replace the species already lost since the end of the Ice Age. This fact has led Norman Myers to pose the following questions:

Is it satisfactory to safeguard as much of the planetary stock of species as possible, or should greater attention be paid to safeguarding evolutionary processes at risk? This is an entirely new way of looking at the world—not in terms of losing species, but in terms of losing pathways of speciation. Perhaps the motto should be "save speciation" rather then "save species." Of prime importance is the question of biodisparity—the number of body types. There could be many species on Earth, but few body types. Is it enough to save a large number of species if we fail to save biodisparity as well? Should the evolutionary "status quo" (the current makeup of the Earth's biota) be maintained by preserving precise phenotypes of particular species that will enable evolutionary adaptations to persist, thereby leading to new species? For example, should two elephant species be maintained, or should we keep the option of elephant-like species in the distant future? Is there some minimum number of individuals necessary not just for the survival of a species, but the survival of the potential for future evolution in that species? Should the slow breeders (the megamammals) be given greater attention than, say, the rapidly breeding insects? Are we in a triage situation?

How do we assess the relative importance of endemic taxa as compared with evolutionary fronts such as origination centers and radiation lineages? Myers thinks it far more appropriate to safeguard the potential for origination and radiation than any individual species. Let endemic taxa go.

This last recommendation is heresy by the rules of modern conservation. It has long been argued that endemic centers—those regions that contain species found nowhere else—are among the most important places to save. But Myers's point is that endemic centers exist because they have not produced large numbers of successful species. Endemic centers are often living museums of ancient species that do not have much potential for future evolution.

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