Saturday, May 15, 2010

Study of Evolution Needed to Understand and Control Plant Diseases, Scientists Argue

A strong argument for the validity of evolution is the fact that our research into diseases and medical treatments assumes that evolution accounts for the divergence of both organisms such as ourselves and disease pathogens. Without this assumption, our medical research would grind to a halt.

An article in Red Orbit, an Internet journal for news on science, space, and technology, Emergence Of Fungal Plant Diseases Linked To Ecological Speciation, discusses the reasoning behind a commentary published by Tatiana Giraud, Pierre Gladieux, and Sergey Gavrilets that argues for the need for funding for general research on evolution. Without understanding evolution, they argue, we would not be able to understand how new diseases emerge, since a new species may provide a new and better host for certain portions of a pathogen community. Pathogens themselves also tend to evolve rapidly.

So when we hobble efforts to teach evolution, we are undercutting the ability of our society to generate scientists capable of studying the one group of nature's organisms which still poses a serious threat to human life. Anti-evolutionary crusaders are also the loudest voices for cutting government and private funding of evolutionary research. A citizenry unaware of the value of understanding evolution will be less likely to object when funding for evolution is cut.

So the next time you come down with a disease and the good doctors at your local hospital quickly identify and treat your disease, say a prayer of thanks for the scientists who have devoted their lives over the past 15o years understanding the nature of evolution! Then next time you hear someone suggest we cut funding for evolution research, ask him or her how Intelligent Design advocates would approach the control of infectious diseases.

This leads me to think about the theology of Creationism and Intelligent Design, which would have us believe that all the diversity of species is purely the result of recent creation of all species by God. Ian Anderson, the driving creative force behind the rock group Jethro Tull, wrote a lyric that goes, "The jungles are full of crocodile nasties/ and he who made kittens put snakes in the grass."

The comedy group Monty Python wrote a parody of the song "All Things Bright and Beautiful," called "All Things Dull and Ugly." Here are the lyrics of the original song (which I remember singing in my church's children's choir):

All things bright and beautiful,
All creatures great and small,
All things wise and wonderful:
The Lord God made them all.

Each little flow’r that opens,
Each little bird that sings,
He made their glowing colors,
He made their tiny wings.

The purple-headed mountains,
The river running by,
The sunset and the morning
That brightens up the sky.

The cold wind in the winter,
The pleasant summer sun,
The ripe fruits in the garden,
He made them every one.

The tall trees in the greenwood,
The meadows where we play,
The rushes by the water,
To gather every day.

He gave us eyes to see them,
And lips that we might tell
How great is God Almighty,
Who has made all things well.

Here is Monty Python's version:

All things dull and ugly,
All creatures short and squat,
All things rude and nasty,
The Lord God made the lot.

Each little snake that poisons,
Each little wasp that stings,
He made their brutish venom.
He made their horrid wings.

All things sick and cancerous,
All evil great and small,
All things foul and dangerous,
The Lord God made them all.

Each nasty little hornet,
Each beastly little squid--
Who made the spiky urchin?
Who made the sharks? He did!

All things scabbed and ulcerous,
All pox both great and small,
Putrid, foul and gangrenous,
The Lord God made them all.

In theological circles, these songs highlight the problem of theodicy, the name given to the question, "If God is a loving God, why do we have such a multitude of evils in the world?" A theology that embraces the findings of science has no need of this question. The evolution of all the things we value most, including ourselves, strawberries, bluebirds, ladybugs, goldfish, and kittens, also produced all the nasty, ugly parts of nature. In Unitarian Universalism, this is referred to as the interconnectedness of all life. Embracing this leads in a very different theological direction than a Creationist theology.

It also means that when we study evolution, we are studying life, ourselves, and--I would assert--God. Other religions, such as Buddhism and Taoism, also embrace the plurality of nature, pointing out that the distinctions between good and bad, beautiful and ugly, medicine and poison, are human inventions, not a part of the natural order. The sooner we recognize this, the more quickly we can approach an understanding of the whole which is both wholesome and healthy.

Thursday, May 13, 2010

Filling in the Gaps

Anti-evolutionists will not be trumpeting this news to their faithful fundies, I don't think. Irish study fills gap in evolution describes a new fossil find, not just a single fossil, but a site that is providing thousands of fossils documenting a stretch early evolution that has not been studied before. As the article reports, fossils of soft-bodied animals are extremely rare. This is because the conditions that will preserve a soft body are extremely rare. Only when the soft bodies are captured in some kind of muck which stops decay and then the muck turns into something like shale do we get to see what these ancient creatures looked like.

Those critical of evolution like to claim that the fossil record is incomplete. They say that as if it were not completely expected and explainable. As described in my previous post, the fossil record shows steady, slow evolution of many species, as well as relatively fast spurts of evolution. What gaps exist are not because intermediate creatures did not exist, but because they were not preserved in fossils or because we have yet to discover where they are preserved.

When new fossils are found, they provide a kind of lab in which to test evolutionary theory (not that more tests are needed, but that is what science always does with new information). We look at what we find and ask if it is consistent with theory. In this case, the fossils found in Morocco show life about 480 million years ago. Another site preserving such soft-bodied species dates back 510 million years ago. If evolution is correct we expect to find some creatures essentially unchanged even over 30 million years. But we also expect some creatures to have evolved to take advantage of new ecological niches.

That is exactly what is being found in the Fezouata Formations in the Draa Valley north of Zagora in southeastern Morocco.

“We know the fossil record is an important record of life, but it is an incomplete record,” says [Dr. Patrick] Orr. It makes interpretation of the progress of evolution very difficult, akin to trying to assemble the plot of a film using only intermittent still images, he suggests.

There was an explosion of new life forms during the Cambrian Period, with the shales revealing soft-bodied animals, according to Orr, “and then the record went blank.”

Now the evolutionary story continues with the Moroccan fossils showing that many of these Cambrian animals survived and multiplied into the next period, the Ordovician. The original animals were there but the Ordovician Period saw a rapid diversification of related species and so the mix is much more varied, Orr says.

This kind of filling in of gaps has been going on since scientists began hunting for fossils. Sometimes a new fossil location forces revision of the story that scientists had developed based on the then existing evidence. But this is a natural part of science. Such revisions are not to the theory of evolution, but to the details of what we are understanding evolution to have entailed.