Late Breaking News

Chapter 3, p.53, 62: A report in the New York Times (Aug. 24, 2001: A12) describes two new estimates on the total number of genes (coding portions of the DNA) in the human genome. Both groups that had been working on the genome estimated a surprisingly low figure of 30,000. It now seems that only about half the genes listed by these groups overlap, meaning that the total is more like 40,000. Moreover, because research into identifying and verifying genes is ongoing, there might be more. It is unlikely, however, that the number would reach the old estimate of 100,000.

Chapter 3 (p. 62) and Chapter 13 (p. 346): Research into the human genome rushes along! Another level of analysis, not specifically mentioned in the text, involves haplotypes. These are long stretches of DNA (even up to 100,000 bases) inherited together at a given location on a chromosome that come in different versions because of distinctive patterns of SNPs. Some haplotypes, however, despite involving large numbers of bases, show surprisingly little variation in humans. These are now thought to be powerful tools for looking into connections between DNA variations and disease. Research into haplotypes, however, presents some ethical questions, since some are population-specific and there is concern that this might be interpreted as claiming that our socially constructed races have biological validity. For a nice discussion, see Science 27 July 2001, p. 583.

Chapter 6 (p. 119): Some new research (Science 10 August 2001, p. 1129) indicates that land plants might be older than previously thought, perhaps as old as 700 million years. If this is the case, they would appear on approximately December 15 of the "cosmic calendar" of Figure 6.4.

Chapters 11 and 12: A report in the 2 August issue of Science, p. 534 discusses research that concludes that the typical craniofacial differences between Neandertals and modern humans arise during early individual development, possibly prenatally. This is taken as evidence that the two groups are separate species. It should be noted, however, that the authors appear to consider the groups as distinct species to begin with, since they use H. neanderthalensis and H. sapiens to name the groups.

Chapter 13 (p. 356): The 2 August 2001 issue of Nature, p. 543 reports on new methods of forecasting probabilities of population growth that predict an 85% chance that the world population will stop growing by the end of the century, may not ever exceed 10 billion, and might even be lower by 2100 than it is now.

Chapter 15 (p. 418): We now know how the Ice Man died. In July, 2001, new X-rays revealed a flint arrowhead in Ötzi's shoulder. No doubt, this contributed to his death, either through fatal bleeding or infection. (See the article in the August 7, 2001 New York Times, p. F2.)

2002 McGraw-Hill Higher Education
Any use is subject to the Terms of Use and Privacy Policy.
McGraw-Hill Higher Education is one of the many fine businesses of The McGraw-Hill Companies.