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I don't know if this is interesting to you, but it is to me.

I recently stumbled across this for the second time, it was published in 1993.

I remembered it because at the time I was dating a mycologist..

.....

Animals and Fungi: Evolutionary Tie?

By NATALIE ANGIER

They may seem awfully vegetative in their habits, and the university

researchers who study them may often be counted as members of the

botany department, but fungi are turning out to be far more closely

related to animals than to plants, scientists say.

In a new analysis of genetic relationships among organisms with

complex cells, including sponges, protozoa, algae, plants and animals,

researchers have concluded that animals and fungi share a common

evolutionary history and that their limb of the genealogical tree

branched away from plants perhaps 1.1 billion years ago. Fungi and

animals then went their own way some undetermined time after that.

The new findings, which appear today in the journal Science, suggest

that the common ancestor of animals and fungi was a so-called protist,

a single-celled creature that very likely possessed both animal and

fungal characteristics -- perhaps spending part of its early life

cycle in a membranous and mobile form resembling a human sperm, and at

a different stage growing a stiff cell wall similar to that seen in

today's fungi. Evolution Study by Genes

The new report did not look at fossil data or physical traits of

organisms, as more traditional taxonomic studies have done, but rather

took the currently popular approach of studying evolution by examining

genes. Through analyzing the same genes in many different species and

tracking how many mutational changes have occurred in the genes from

one organism to the next, scientists are able to calculate kinships

based on complex mathematical models rather than on an eyeball

appraisal of how species look.

In this case, the reckoning overturned previous evolutionary trees

that for any number of anthropocentric reasons, had placed the

kingdoms of fungi and animals very far apart.

The discovery was greeted with enthusiasm by many mycologists, the

specialists who study fungi and who long have felt their field has

been ignored in favor of animal science. New Status for Mycology

" I think this is very interesting, and it's quite gratifying, " said

Dr. W. of the University of California at Berkeley.

" Perhaps it's time for us to move out of the botany department and

into the zoology department. "

Or better yet, he said, to promote mycology to a status worthy of its

own department. Dr. is a mycologist, but his title is professor

of plant biology. And he admits that convincing people that they have

anything in common with a mushroom, a packet of baker's yeast, or a

bloom of mold on an fetid piece of cheese will take some doing.

Researchers said, however, that the evolutionary affinity between

animals and fungi could explain why fungal diseases in humans are so

difficult to treat. " A lot of the metabolism is so similar that you

can't target a fungus sufficiently without gravely affecting the human

host as well, " said Dr. L. Sogin of the Center for Molecular

Evolution at the Marine Biological Laboratory in Woods Hole, Mass.,

the main author of the new report.

Fungal diseases are a particularly severe problem in those with

suppressed immune systems, including AIDS patients and people who have

had organ transplants.

Dr. Sogin also suggested that the new results will buttress

long-standing arguments among yeast geneticists that fungal cells

offer a wonderfully tractable way of looking at essential biological

problems of relevance to humans.

" If you're looking for precursors to the nervous system, you might

consider looking for them in fungi, " he said.

Citing another example of how fungal cells can yield benefits for

human studies, Dr. Gerald Fink, director of the Whitehead Institute

for Biomedical Research in Cambridge, Mass., and a yeast geneticist,

pointed out that there is a mutation in yeast cells much like the one

that gives rise to Lou Gehrig's disease, a fatal neurodegenerative

disorder. The new discovery of kinship, he said, " just shows once

again that yeast is a perfect model for man, " adding, " I feel

vindicated. " Agreement and Discord

Another report by scientists at Indiana University in Bloomington, now

under consideration for publication by a major scientific journal,

also reaches the conclusion that fungi and animals are closely

related.

But molecular geneticists working in the laboratory of the late Allan

of the University of California at Berkeley, who before his

death in 1991 was a celebrated proponent of looking at genes for clues

to evolution, said their analysis of the molecular data contradicts

the latest report. They said their study places animals and plants

together in a group, with fungi having branched off from the tree

earlier.

" Mitch Sogin's results aren't significant and he's over-interpreting

his data, " said Arend Sidow, a graduate student working at Berkeley on

molecular evolution. But Mr. Sidow's results have yet to be published

and thus scientists said it was impossible to judge the merits of his

claim.

In the new study, scientists considered the genes that produce

so-called ribosomal RNA, a component of the protein-making factories

found in all living cells. They compared the genes from dozens of

species of eukaryotes, a group of organisms with complex cellular

structure that includes everything from yeast to plants to mammals.

Many of the eukaryotes the scientists considered were obscure

creatures like choanoflagellates, microscopic beings surrounded by

tentacle structures, but they did include in their analysis such

familiar species as frogs and jellyfish.

Through comparing changes that occurred in the ribosomal genes, the

scientists were able to piece together an evolutionary tree for the

vast group of eukaryotic organisms.

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