Ernst Mayr, Agassiz professor of zoology, emeritus, is affectionately known as Darwin's modern day bulldog. And at 90 years of age, this bulldog has no intentions of slowing down.

Stephen Jay Gould, Mayr's successor to the Agassiz professorship, wrote in the February issue of the science journal Evolution that 1904 was significant for being the year the ice cream cone was invented and the first Olympic games were held in America.

But for biology, writes Gould, the "cardinal event" was the birth of Ernst Mayr.

In fact, the entire issue of Evolution was devoted to celebrating Mayr's 90th birthday. Mayr served as the magazine's first editor in 1947.

Mayr, an evolutionary biologist, flew to Japan last month to accept the latest of his more than 25 awards--the 1994 International Prize for Biology.

Mayr won the prize for his work in systematics, which attempts to define the evolutionary relationships between organisms.

"He's got every kind of prize in the world," says John R. Pappenheimer '36, Higginson professor of physiology.

The prize, which is awarded by the emperor and empress of Japan, is regarded as one of the top prizes in biology. The medal is accompanied by a monetary award of 10 million yen, or about $100,000.

Mayr is the second Harvard professor to win the award. Baird Professor of Science Edward O. Wilson won it in 1993.

"There is no Nobel prize in biology, so this is the best," says Walter J. Bock, professor of evolutionary biology at Columbia University. Bock, a former student of Mayr's, served on the 17-member committee that selected Mayr for the prize.

"Clearly, he is one of the outstanding evolutionary biologists," says Bock. "He laid down the foundation of modern synthesis [thinking]."

Mayr almost declined to answer when asked why he thought he was selected for the award this year.

"If I tell you why I was chosen, you'll say 'What a conceited ass he is,'" Mayr says. "The fact is that I was the best of the nominees."

And Mayr can say that without grinning. In fact, he is widely regarded as one of the best in his field.

According to the Committee for the International Prize for Biology, Mayr has described 26 currently recognized species of birds, more than any other living ornithologist,