April 29, 1997

Three competing hypotheses now dominate debate about cause of mass extinction of scores of species of large North American mammals about 13,000 years ago; one camp contends that rapidly changing climate at end of last ice age did in the Pleistocene megafauna, as they are called, by transforming their habitat; opposing camp points out that extinctions closely followed animals' first contact with modern humans and suggests that megafauna were hunted to extinction; third and newest hyphothesis is that animals were killed by rampant disease carried by dogs, rats, birds, parasites or other living baggage that accompanied first human arrivals; some scientists suggest that climate, hunting and disease may all have played role in extinctions; diagrams; photo (L)

Senator Alfonse M D'Amato stakes out significantly more moderate position on New York State's rent laws than State Senate's majority leader Joseph L Bruno, a fellow Republican; he strongly hints that he was prepared to exert his considerable influence to negotiate compromise if talks remain stalemated (M)

Dan Persky, campaign chairman for State Senate candidate Don Hurley, is fighting Longport, NJ, local ordinance that bans posting campaign literature until 30 days before election (New Jersey Daily Briefing) (S)

Growing link between drug industry and academia may be affecting reliability of information provided to doctors and the public about drugs and other medical therapies; many medical leaders have expressed concern that reluctance of scientists and journal editors to publish studies that do not show any benefits from drug or therapy significantly skews information available to doctors and public; now there is new concern: possible influence of contracts between drug companies and academia in creating such biases; in latest instance, university scientist's findings about common thyroid drug were suppressed by company that paid for research; Dr Mary K Pendergast, Deputy Commissioner of Food and Drug Administration, says there is no way of knowing how often restrictive clauses prevent academic investigators from publishing information that companies want suppressed if they perceive it will threaten their commercial interests (M)

Dow Industrials Up 44.15, With Banking Issues Strong Blue-chip stocks rallied, with the Dow industrials rising 44.15 points, to 6,783.02. The market overcame a selloff in Boeing to snap a three-session losing streak. Interest-rate-sensitive stocks, such as those of banks, American Express and Travelers Group, which could suffer should inflation rise, were strong, showing that there is confidence in the market's prospects. $(Page D12.$) Treasury prices rose, with the 30-year bond yield slipping to 7.11 percent from 7.14. $(D19.$)