life11e_ch01

Biology can inform public policy

Thanks to the deciphering of genomes and our newfound ability to manipulate them, vast new possibilities now exist for controlling human diseases and increasing agricultural productivity—but these capabilities raise ethical and policy issues. How much and in what ways should we tinker with the genes of humans and other species? Does it matter whether the genomes of our crop plants and domesticated animals are changed by traditional methods of controlled breeding or by the biotechnology of gene transfer? What rules should govern the release of genetically modified organisms into the environment? Science alone cannot provide all the answers, but wise policy decisions must be based on accurate scientific information.

Biologists are increasingly called on to advise government agencies concerning the laws, rules, and regulations by which society deals with the increasing number of challenges that have a biological basis. As an example of the value of scientific knowledge for the assessment and formulation of public policy, consider a management problem. Scientists and fishermen have long known that Atlantic bluefin tuna (Thunnus thynnus) have a western breeding ground in the Gulf of Mexico and an eastern breeding ground in the Mediterranean Sea (Figure 1.15). Overfishing led to declining numbers of bluefin tuna, especially in the western-breeding populations, to the point of these populations being endangered.

Figure 1.15 Bluefin Tuna Do Not Recognize Boundaries (A) Marine biologist Barbara Block attaches computerized data-recording tracking tags to a live bluefin tuna before returning it to the Atlantic Ocean, where its travels will be monitored. (B) Tracking data from eastern (Mediterranean) and western (Gulf of Mexico) breeding populations of bluefin tuna. At one time commercial fishing regulatory agencies assumed that bluefins from western- and eastern-breeding populations fed on their respective sides of the Atlantic. To speed recovery of the endangered western population, fishing quotas were created for each side of the mid-Atlantic Ocean (dashed line).

Question

Q: Based on Dr. Block’s data, does it seem likely that fishing quotas based on the mid-Atlantic boundary line would protect the western-breeding population of bluefin tuna?

The data reveal that the eastern- and western-breeding populations of bluefin tuna share the same mid-Atlantic feeding ground. Since the western-breeding population is commonly found east of the boundary line, the imposition of restrictions west of the boundary line would not have been effective in protecting the western-breeding population.

Initially it was assumed by scientists, fishermen, and policy makers alike that the eastern and western populations had geographically separate feeding grounds as well as separate breeding grounds. Acting on this assumption, an international commission drew a line down the middle of the Atlantic Ocean and established strict fishing quotas on the western side of the line, with the intent of allowing the western population to recover. Modern tracking data, however, revealed that in fact the eastern and western bluefin populations mix freely on their feeding grounds across the entire North Atlantic—a swath of ocean that includes the most heavily fished waters in the world. Tuna caught on the eastern side of the line could just as likely be from the western-breeding population as the eastern; thus the established policy could not achieve its intended goal.

Scientific knowledge can make significant contributions to the formulation of wise public policy, but economic and political factors frequently outweigh scientific recommendations. It is particularly lamentable when solid scientific evidence is discounted or ignored because it is inconvenient. An example is the rejection by many policy makers of strong evidence for and scientific consensus on global climate change.