(UPDATED) Another half-brained science headline

This is why anyone who uses the usual mainstream media outlets for information is wasting his or her time. Unfortunately, the average Joe Six-Pack won't be inclined to pick up a scientific journal when with the tap of a remote button he can turn to places like Fox News.

But that's journalism for you; the one with the most interesting news wins, no matter how factual it actually is.

I accept the Hennigian idea that when speciation occurs, the ancestoral species goes extinct, and becomes hypothetical because it cannot be identified with certainty. Of course, the stickleback fishes have never heard of Hennig; but still, I do not like to see references to living ancestral species.

Jim Thomerson said: I accept the Hennigian idea that when speciation occurs, the ancestoral species goes extinct, and becomes hypothetical because it cannot be identified with certainty. Of course, the stickleback fishes have never heard of Hennig; but still, I do not like to see references to living ancestral species.

Seems someone at Nat Geo needs to read a copy of The Ancestor's Tale by R. Dawkins. He notes many times that evolution, thus far, has never went retrograde and then resumed its course (i.e., bats don't cease flying, start walking, then resume flying again--forgive me if I simplify a bit!). Thus, the discovery of a walking ancestor prior to the advent of flight doesn't upend any aspect of evolution, if I'm reading my Dawkins rightly.

Pardon my slip:

Read "gone retrograde"

Trigger finger on the "submit!"

As I understood Hennig's argument, he was thinking of allopatric speciation. If a species gets separated into two populations, and speciation occurs, then there are two new species, not one new and one old. I thought his argument as to why was kind of fuzzy, and cannot recall the substance of it. I regard it as a convention which allows us to draw trees with all the species at tips of branches. As I mentioned, I was well aware of various cladistic theories for more than 30 years before I published a cladistic analysis. I was not an easy convert.

Has anyone politely notified the NG News of this faux pax?
They're generally pretty understanding and not liking to make mistakes.

DavidK said: Has anyone politely notified the NG News of this faux pax? They're generally pretty understanding and not liking to make mistakes.

RBH -

Count your blessings, I suppose. It could have been another Darwinius.

Appreciatively yours,

John

Flight is expensive (requires vast amounts of energy), when, in the evolutionary context, it can at all be done away wtih, it is; Galapogas birds, many NZ birds etc.
The walking bats of NZ simply have found that finding their food without flying tends to increase their breeding potential; more energy for offspring. Unfortunately this process begun well before the Maori and Europeans (and their dogs, cats, rats, possums, rabbits, ferrits etc) arrived has left them open to predation, and competition, which they are ill-evolved to counter. Like so many of NZ's flightless birds they appear to be headed for extinction.

JEB--
As I understand Dawkin's point, there is no logical reason evolution couldn't go retrograde and then resume its course. There are simply so many possible combinations of alleles in 25,000 to 30,000 genes (I think that's about the number you'd expect to find in a mammal)that the probability of choosing the same path three times (once in reverse) is vanishingly small-- undoubtedly smaller than one over the total number of atoms in the universe.

But as far as gross anatomy is concerned, traits do waver back and forth, like the bills of Galapagos finches that get larger, smaller, larger again with cyclical climate variations. There's nothing to prevent a line of species from developing a trait, losing it when it is no longer adaptive, and then having some distant descendant develop something vaguely like it later. For instance, whales re-evolved fins, which are not identical to the fins of their fish ancestors, but do serve the same purpose. The NG headline writer could just as easily have said "Whale fins upend evolutionary theory," except that people are more familiar with whales, so they'd catch on to the scam too fast.

The frequency with which headlines trumpet "upended" evolutionary theory, shocked scientists, etc., etc., is an indication of just how pernicious the creationist movement has become.

National Geographic should issue a formal retraction and an apology.

Cue Casey Luskin's breathless DI posting about Evolution Upended in one, two, three. . . . . . . .

Jim Thomerson said: I accept the Hennigian idea that when speciation occurs, the ancestoral species goes extinct, and becomes hypothetical because it cannot be identified with certainty. Of course, the stickleback fishes have never heard of Hennig; but still, I do not like to see references to living ancestral species.

hoary puccoon :

Thanks for the clarification. It has been some years since I read the good doctor's book, so I relied on a foggy memory without directly referencing the text. Nonetheless, once I fished AT off my shelf and scanned back through the relevant passages, it is clear that you are spot on with regards to Dawkins pointing out the enormity of odds for evolution to ever occur multiple times in the same fashion.

John Harshman said:

Jim Thomerson said:

I'm pretty sure there's no chance of interbreeding, or of determining whether thery're potentially interbreeding. Messy stuff, species.

JEB said: Seems someone at Nat Geo needs to read a copy of The Ancestor's Tale by R. Dawkins. He notes many times that evolution, thus far, has never went retrograde and then resumed its course (i.e., bats don't cease flying, start walking, then resume flying again--forgive me if I simplify a bit!). Thus, the discovery of a walking ancestor prior to the advent of flight doesn't upend any aspect of evolution, if I'm reading my Dawkins rightly.

In the UK it is the norm to have a headline writer for newspaper articles - the author might make a suggestion but I suspect not many of them bother! It is the headline writer, guided by editorial policy, who actually sets the wording. I have seen headlines that bore no relationship to the body of the story.

But it occasionally seems to work. American brown bears are ancestral to polar bears, because polar bears are more closely related to some brown bears than to others. Are American brown bears a species? Did they stop being a species when one population diverged? Clearly brown bears are a single morphospecies, including the ancestral population, and polar bears another.

Alan B said: In the UK it is the norm to have a headline writer for newspaper articles - the author might make a suggestion but I suspect not many of them bother! It is the headline writer, guided by editorial policy, who actually sets the wording. I have seen headlines that bore no relationship to the body of the story.

Rob said:

John Harshman said:

Jim Thomerson said:

I'm pretty sure there's no chance of interbreeding, or of determining whether thery're potentially interbreeding. Messy stuff, species.

There is a nice wikipedia entry on Polar bear Grizzly bear hybrids (Pizzly or Grolar bear) in nature and captivity.

So species are not necessarily monophyletic (if that’s the right word).

The world can be changed by man's endeavor, and that this endeavor can lead to something new and better .No man can sever the bonds that unite him to his society simply by averting his eyes . He must ever be receptive and sensitive to the new ; and have sufficient courage and skill to novel facts and to deal with them .

Amy said: The world can be changed by man's endeavor, and that this endeavor can lead to something new and better .No man can sever the bonds that unite him to his society simply by averting his eyes . He must ever be receptive and sensitive to the new ; and have sufficient courage and skill to novel facts and to deal with them .

RBH said: That's also the case in the U.S., which is why I was careful to distinguish between the headline and the article itself. (Though clueless editors have been known to piss in perfectly good articles, rendering them substantively incoherent.)

Mike of Oz said:

RBH said: That's also the case in the U.S., which is why I was careful to distinguish between the headline and the article itself. (Though clueless editors have been known to piss in perfectly good articles, rendering them substantively incoherent.)

So too, Down Under.

What I would say about the bear situation accepting what is said here as facutal (not knowing any better). If they were fishes, and the polar bear is accepted as a species, then the most closely related brown bear population is a sister species and should be recognized as such. Sister species cannot be ancestors. By sister species, I mean that the polar bear and the brown bear species origninated from a unique commen acestor,now extinct, not ancestral to any other species of bear. What this does to the taxonomy of the other brown bear populations, I don't know enough facts to say.

I think most animal taxonomists hope that their taxa are monophyletic. If not, we are into paraphyletic or polyphyletic taxa. I understand that about 25% of higher plant species are of hybrid origin, ie not monophyletic, and this is perhaps the case in some animal species.

As said, ability to interbreed is a plesiomorphous character, so it is best not to define a species, as some the early workers did, as an interbreeding entity. Inability to interbreed is; however, generally accepted as evidence of separate species. The question of interbreeding and speciation is interested and more complicated than one might think. Based on my own work, I accept as good species both sister species which cannot interbred and sister species which have full interfertility in the lab. No foolish consistancy for me. It depends on the situation in nature.

Jim Thomerson said: If they were fishes, and the polar bear is accepted as a species, then the most closely related brown bear population is a sister species and should be recognized as such. Sister species cannot be ancestors. By sister species, I mean that the polar bear and the brown bear species origninated from a unique commen acestor,now extinct, not ancestral to any other species of bear.

I think most animal taxonomists hope that their taxa are monophyletic.

As said, ability to interbreed is a plesiomorphous character, so it is best not to define a species, as some the early workers did, as an interbreeding entity.

Inability to interbreed is; however, generally accepted as evidence of separate species. The question of interbreeding and speciation is interested and more complicated than one might think. Based on my own work, I accept as good species both sister species which cannot interbred and sister species which have full interfertility in the lab. No foolish consistancy for me. It depends on the situation in nature.

RDK said: ... the one with the most interesting news wins, no matter how factual it actually is.

John, I think you typed synaporphy when you ment autapomorphy. I don't agree with the extreme application of the if it has an autapomormhy it is a separate species, but I understand the argument.

Most of my work has been at the species identification level, mostly killifish, predominately Rivulids. So far as I know, there are no fossil Rivulids.

Consider Pterolebias hoignei and P. zonatus (now in Ganatholebias); these are sister species by two independent DNA studies, and morphologists agree. The range of P. hoignei is included in the range of P. zonatus. They are ecologically separated, and were initally thought to be ecophenotypes of a single species. They can be diagnosed, and I recognized them as separate species. Turns out they will not hybridize under lab conditions where both species breed prolifically. In the wild they have different breeding behavior. P. hoignei has 46 chromosomes; the males have a large Y chromosome. P. zonatus has 42 chromosomes and no obvious sex chromosomes.

Fundulus notatus and F. olivaceous, are they separate species? They have large oerlapping ranges but seldom occur together (I think 19 localities of syntopy are now known). I raised hybrids, F2's and backcrosses to see what they looked like. I used fishes from allopatric populations so that I would be sure of identification. Later workers, using fish from proximal populations, have had little success going beyond the F1. It turns out that there are a small number of natural hybrids in some of the 19 areas mentioned above. Hybrids are relatively rare, There is a little mitochondrial gene intogression but no nuclear gene intogression beyond the area of syntopy. Turns out that F. notatus has 40 Chromosomes and F. olivaceus has 48. It is a mater of Robertsonian fusion. In F1 meiosis, two little acrocentrics line up with with a big metacentic.

Until recently, we did not have robust phylogenies for the Rivulidae, so thinking phlogenetically was hard. At the time I worked on the Fundulus, the same was true of the Fundulidae.

Jim Thomerson said: John, I think you typed synaporphy when you ment autapomorphy.

Consider Pterolebias hoignei and P. zonatus (now in Ganatholebias); these are sister species by two independent DNA studies, and morphologists agree.

The range of P. hoignei is included in the range of P. zonatus. They are ecologically separated, and were initally thought to be ecophenotypes of a single species. They can be diagnosed, and I recognized them as separate species. Turns out they will not hybridize under lab conditions where both species breed prolifically. In the wild they have different breeding behavior. P. hoignei has 46 chromosomes; the males have a large Y chromosome. P. zonatus has 42 chromosomes and no obvious sex chromosomes. Fundulus notatus and F. olivaceous, are they separate species?

Of course, I don't accept any of your three options, and do not understand why you offered them.

The DNA studies are available on line. Google DNA and Rivulidae. I'm not the DNA guy, but for one of the two studies, where the DNA guy was involved in field work, our goal was ten individuals from each population. The situation with the wide ranging P. zonatus was that there were small DNA differences among populations, correlating with geographical separation. Same was true of the wide ranging Rachovia maculipinna.

Do you study Ratites?

Jim Thomerson said: Of course, I don't accept any of your three options, and do not understand why you offered them.

The DNA studies are available on line. Google DNA and Rivulidae. I'm not the DNA guy, but for one of the two studies, where the DNA guy was involved in field work, our goal was ten individuals from each population. The situation with the wide ranging P. zonatus was that there were small DNA differences among populations, correlating with geographical separation. Same was true of the wide ranging Rachovia maculipinna.

Do you study Ratites?

Well, I have not encountered the situation you mention, or did not recognize it, if I did. Actually, the sticklebacks , where oicalized freshwater species bud off the widespread marine species, may be an example. Fortunately, my only encounter with sticklebacks is that I saw some swimming in the moat around Wells Cathedrial in England.

You had asked about the number of individuals used in DNA analysis. In the family level phylogenies of the Rivulidae there are species represented by a single individual, which one hopes is better than nothing. As I have had it explained to me, the more individuals, the more populations, the more taxa and the more bases included in the analysis, the more robust the analysis is likely to be.

Hennig made the point, very often ignored, that one should be very familiar with the group before attempting cladistic analysis. I have tried to follow that and become very familiar with my fishes before deciding which philosophy will allow me to best express what I know about them.

Did you work at the Field Museum at one time? I was a Research Associate in Fishes there for many years.

Jim Thomerson said: Well, I have not encountered the situation you mention, or did not recognize it, if I did.

Did you work at the Field Museum at one time? I was a Research Associate in Fishes there for many years.

Barry once commented to me, "I've collected extensively in the same areas of Venezuela where you are describing all these new species and I've never seen a single one." Barry was out in the big rivers while I was in swamps, temporary pools, and little streams. Sort of like the blind men describing an elephant.

I was at Southern Illinois University at Edwardsville. I figured I should work on fishes which occupy marginal habitats, rather than trying to compete with all the big guns working out in the mainstream. Worked out good for me.

Barry once commented to me, “I’ve collected extensively in the same areas of Venezuela where you are describing all these new species and I’ve never seen a single one.” Barry was out in the big rivers while I was in swamps, temporary pools, and little streams. Sort of like the blind men describing an elephant.