JOHN YDSTIE, host:
Okay, students, whoever knows who Carl Linnaeus was and what he did, please, raise your hand. Well, not many hands there. For those of you who made paper airplanes during science class, Linnaeus was the Swedish botanist who invented the modern classification of plants and animals. He was also the first to say that plants reproduced sexually. This prompted, at least, one contemporary critique of whom he had many to ask who would have thought that bluebells, lilies and onions could be up to such immorality. This is the 300th anniversary of Carl Linnaeus' birth.
And joining us to talk about the man and his legacy is Dr. Robbin Moran, a curator at the New York Botanical Garden. Welcome to the program.
Dr. ROBBIN MORAN (Curator, New York Botanical Garden): It's nice to be here.
YDSTIE: Linnaeus' thoughts and writings about plants were filled with images of human sexuality right from the beginning. Pretty racy stuff for Europe three centuries ago, I would think.
Dr. MORAN: That's correct. And as a young student, he handed in to his major professor a thesis on sexuality in plants, and this got across the idea that plants reproduce sexually. And therefore, since that's such an important biological function that classification of plants should be based on the sexual organs, that is, the stamens, the pollen-producing organ, and the pistils, the fruit and seed-producing organs of the flower.
YDSTIE: He writes: The actually petals of a flower contribute nothing to generation, serving only as a bridal bed, which the great creator has so gloriously prepared, adorned with such precious bed curtains and perfumed with so many sweet scents in order that the bridegroom and bride may therein celebrate their nuptials with greater solemnity.
Dr. MORAN: Yeah. And some people might construe that as botanical pornography, and that did offend people during his time. And really, one of the biggest objections to Linnaeus' sexual system of plant classification based on the number of stamens and pistils was that the system was immodest and you couldn't teach it to women.
YDSTIE: He named plants and animals according to genus or group and species or kind - that was revolutionary for that time.
Dr. MORAN: It was, and it seems so second nature to us today, but it really was revolutionary and very different. Previously, they had used long names that were called polynomials or phrase names. And these consisted of the genus name, the kind of organism, plus a string of words that described the plant or animal and distinguished it from everything else in the same genus. And they were very long names, these polynomials and let me just…
YDSTIE: Give us an example. Yeah.
Dr. MORAN: Sure. Here's one for the white clover that calmly grows in lawns here in the United States. The polynomial name was trifolium capitulus ambelerabus, leguminous tetrospermus, coli repenti(ph). When Linnaeus invented the system of binomial nomenclature - two word names - he just called that trifolium repens.
YDSTIE: Much simpler.
Dr. MORAN: Yes. And he got even with his critics in a very interesting ways, really only a taxonomist can. He named unattractive, unpleasant plants and animals after his critics. For example, he named the toad genus after Buffon, the great French naturalist Buffon who he didn't see eye-to-eye with on a lot of matters. He named a smelly weed that has these hairs that exude drops of brown, viscous, smelly liquid. He named that after a Professor Sizebeck(ph). It's the genus sizebekia(ph).
YDSTIE: How much of Linnaeus' classification system remains in modern botany?
Dr. MORAN: Well, we use a system of binomial nomenclature, this formal system. His sexual system of classification was replaced about 1820 by a different kind of classification that relied on more characters than just the stamens and the pistils in the flower. So it's really not used today, but his system of naming has.
And you know, another interesting story about Linnaeus is that he was the first to record temperatures in the scale that we use today in degrees centigrade. We usually say degrees Celsius because there was a Swedish scientist who was a friend and contemporary of Linnaeus', Anders Celsius who designed a centigrade thermometer.
But Celsius had zero as the boiling point of water and 100 as the melting point of water. And Linnaeus was the first to have a centigrade thermometer built with the scale of how we use it today. And he was the first to record temperatures in degree centigrade or degree Celsius the way we use them today.
So really what we use today, I think, is Linnaeus thermometer and maybe you can make the argument that we should be calling it degrees Linnaeus.
YDSTIE: Thanks very much, Dr. Moran.
Dr. MORAN: You're most welcome.
YDSTIE: Dr. Robbin Moran is a curator at the New York Botanical Garden.