Snail Darters and the economic impact of taxonomy

I grew up in East Tennessee and graduated from UT-Knoxville in 1977. I recall the episode of the Snail Darter and the Tellico Dam project. The Darter was considered an endangered species at the time, and a lawsuit to protect it held up dam construction for awhile. In the event, the Darter was relocated and the dam was built.

At that time, the principal tool for taxonomic classification of species was morphology, the same approach used by Carl Linnaeus. Yes, protein sequencing—particularly of Cytochrome C—was starting to come into use, but it was new back then. And genomics was in the distant future.

Now a new study using both morphometric and genomic analyses calls into question whether the Snail Darter is/was a unique species:

“We present a comparative reference-based taxonomic approach to species delimitation that integrates genomic and morphological data for objectively assessing the distinctiveness of species targeted for protection by governmental agencies. We apply this protocol to the Snail Darter (Percina tanasi), a freshwater fish from the Tennessee River that was discovered in 1973 and declared an endangered species under the ESA in 1975. Concurrently, the Snail Darter’s habitat was slated to be destroyed through the construction of the Tellico Dam by the Tennessee Valley Authority (TVA), inspiring nationwide protests advocating for the suspension of the federal project. This David versus Goliath struggle between supporters of the 3-inch fish and the TVA culminated in the first major legal conflict over protections afforded by the ESA, the US Supreme Court case Hill v. TVA, 437 U.S. 153 (1978), with a 6 to 3 ruling in favor of protecting the Snail Darter and interrupting the completion of the Tellico Dam. Here, we integrate multiple lines of evidence in a comparative framework to demonstrate that despite its legacy, the Snail Darter is not a distinct species but is a population of the Stargazing Darter (Percina uranidea) described in 1887.”

The lesson here is not that science is not to be trustworthy. It’s that scientific conclusions are provisional and about the weight of evidence. When new evidence appears that falsifies previous hypotheses, scientific conclusions can and should be revised in light of the new data and political decisions revised accordingly.

https://www.cell.com/current-biology/fulltext/S0960-9822%2824%2901593-8

 

Comments

Post a Comment

Popular posts from this blog

Two sides

Image
  Yes, there are two sides to every question. In most cases, there is a correct side and a wrong side. In the case of Kamala Harris, the correct side is that she was born a US citizen. The wrong side is that her parents had to be citizens or permanent residents for her to be a citizen. President Trump pretended to be unsure about this, just as he pretended for five years that Barack Obama is not a citizen. In the case of the Harris noncitizen claim, it is backed by the racist C laremont Institute: "The Claremont Institute masquerades as an intellectual salon of the right, but it is really just a racist fever swamp with deep connections to the conspiratorial alt-right. It even granted a fellowship to Jack Posobiec, who helped promote the notorious Pizzagate conspiracy theory. Claremont’s resident bigots offer deranged fantasies of violently expelling Americans from their home country because of their ethnic backgrounds. Their work deserves the intellectual weight given to that of D...
Read more

Who chooses?

Over at jabberwocking.com , Kevin Drum blames pro-choice writers for failing to make the case for reproductive choice. Well, from everything I've read, a clear majority of Americans believe that Roe should still stand. Seems like the case has been made, and if we lived in a truly representative democracy, a limited national right to abortion would be preserved. But beyond that reality, I think Drum has it exactly backwards. Why does the burden of proof fall on those advocating for personal autonomy? Seems to me the null hypothesis is that women should be allowed to make decisions about their own health, and that the justification for nanny state intrusion into such decisions rests with the minority who assert state coercion. Democrats need to hammer on the right-wing GOP to explain why the government takes temporary custody of pregnant Americans. https://jabberwocking.com/liberals-really-suck-at-defending-abortion/
Read more

Black Earth

 Just finished reading “Black Earth: The Holocaust as history and warning” by Timothy Snyder. It is a detailed account of the Holocaust, as well as an effort to abstract lessons from this history for our time. Like his book “Bloodlands,” Snyder’s “Black Earth” makes for painful reading. As the grandson of a Ukrainian Jew and the son of a Jew, I would have been targeted in the Holocaust had I been in the wrong place. I had read several histories of Europe in World War II that included the Holocaust. I knew the basic story of the Holocaust and Hitler’s anti-Semitic vision. I learned a great deal by reading this book. I won’t belabor the ghoulish atrocities committed by the Nazis and their collaborators. To summarize them here would be to trivialize the enormity of the crimes and invite pointless debate about who did what and who suffered more. You’ll have to read the book to understand Snyder’s historical insights. However, I learned many things that I did not know by reading thi...
Read more