Macroevolution: Its all around us...

OK. For all of you that would deny speciation (= macroevolution) is occuring all around us, all the time, check this out - from the current volume of "Science", a *somewhat* respected publication, even among non-scientists.Assortative Mating in Sympatric Host Races of the European
Corn BorerThibaut Malausa,1,2* Marie-There`se Bethenod,3
Arnaud Bontemps,1,3 Denis Bourguet,2 Jean-Marie Cornuet,2
Sergine Ponsard1ABSTRACT
Although a growing body of work supports the plausibility of sympatric speciation
in animals, the practical difficulties of directly quantifying reproductive
isolation between diverging taxa remain an obstacle to analyzing this process.
We used a combination of genetic and biogeochemical markers to produce a
direct field estimate of assortative mating in phytophagous insect populations.
We show that individuals of the same insect species, the European corn borer
Ostrinia nubilalis, that develop on different host plants can display almost absolute
reproductive isolationthe proportion of assortative mating was >95%even in the absence of temporal or spatial isolation.Science 2005, v308: 258-260.Let me spell this out for you.As the insects feed on different plants, they seek mates only on those plants. This 'host plant fidelity' serves as a wedge to separate populations, preventing gene flow between them. Once you have no more gene flow between plant-associated populations, 'poof' you have separate species. It's almost as awe-inspiring as the 'poof' of creation in which all species were instanteously created in immutable forms....

Quoting.....Songbird shows how evolution worksScientists may be witnessing one of the fundamental forces of evolution: the divergence of one species into two.The new data comes from the songs of the greenish warbler, a bird that lives in the foothills of the Himalayas. Researchers have noticed that its song changes gradually throughout its territory.At the extreme ranges of its habitat, the greenish warbler will sing very different songs. This means there are some birds in the territory which, although they belong to the same species, will not mate because they do not recognise each other's calls. Eventually, the two singing groups will become two separate species....Read the complete article at:http://news.bbc.co.uk/1/hi/sci/tech/1123973.stm

I am ready. Still waiting for the first nibble, though.I originally thought that ongoing speciation would be a controversial topic for all creationists, but I have recently learned that some have circumvented this (to me) undeniable contradiction with creation by claiming that it was only the higher 'kinds' of organisms (approximately family level) that were 'created', species being free to 'change' and 'diverge'. A convenient cop-out I suspect, in the face of insurmountable evidence. Holding creation responsible only for higher taxa conveniently re-inforces their contention that 'missing links' are everywhere. Its of course impossible to demonstrate macroevolution occurring in real time at higher taxa...

What's your point?
Ants sometimes drink plant sap?

That looks a lot like a grape leaf.
The "cellulose projections" you describe sound a lot like domatia,
that grape leaves are known to have.
They actually serve as refuges that protect predatory mites on the plant.
Payoff for the plant is they eat the plant-feeding mites.Here is an abstract describing the significance of domatia for plants.http://www.amjbot.org/cgi/content/abstract/85/1/70Now, as for the ants, most are very generalist, opportunistic feeders. They will puncture plant veins and drink sap for the sugar content. Matter of fact, so do many other, normally predatory insects. However, speciation mediated by host plant fidelity only works for specialized plant feeders with very narrow host ranges. Your ants may keep returning to the same plant where they have opened some feeding sites, but that is just becuase they are following a chemical trail laid down by the original foragers that cut the holes, not because adjacent plants wouldn't necessarily be suitable for feeding in the same way. Also, since ants are eusocial insects all those foraging workers are sterile - speciation via host plant fidelity is a mechanism whereby reproductive insects encounter mates that orient specifically to the same species of plant.Hope you find this informative.PS: How do you paste a picture into a post like that?
My computer wouldn't let me.
Wanted to post a picture of a ladybeetle drinking from a plant.This message has been edited by EZscience, 04-19-2005 07:47 AM

Yes, but unfortunately visually-based species recognition is being threatened by human activity causing eutrophication in the lake.see:
Just a moment..."Cichlid Fish Diversity Threatened by Eutrophication That Curbs Sexual SelectionOle Seehausen, * Jacques J. M. van Alphen, Frans WitteCichlid fish species of Lake Victoria can interbreed without loss of fertility but are sexually isolated by mate choice. Mate choice is determined on the basis of coloration, and strong assortative mating can quickly lead to sexual isolation of color morphs. Dull fish coloration, few color morphs, and low species diversity are found in areas that have become turbid as a result of recent eutrophication. By constraining color vision, turbidity interferes with mate choice, relaxes sexual selection, and blocks the mechanism of reproductive isolation. In this way, human activities that increase turbidity destroy both the mechanism of diversification and that which maintains diversity. "This really ties in to another thread we have going under 'sexual selection'. In this case, sexual selection is essential to the maintenance of species identity.

Let's make sure we are talking about the same thing.
Here I simply use macroevolution to refer to the process of speciation.
We can definitely observe that happening in some cases.
And thatis not equivalent to microevolution or 'intra-specific variation'. Also, you talk about hybridization as a path to new species, but it probably isn't an important mechanism in nature.
Factors leading to reproductive isolation of sub-populations in space
and time are.If you are talking about macroevolution in terms of the divergence of higher level taxa over evolutionary time, then I agree that is not something we can directly observe or test with extant life. We can directly view the process of speciation, but nothing beyond.However, different 'taxonomic distance' estimates can be inferred indirectly w/r/t the degree of relatedness of high level taxa and the degree to which they converge on a single 'tree' can give us some degree of confidence in that tree. Genetic markers and sequences are especially valuable in this regard and can generate very plausible phylogenetic trees for higher level taxa. Are they testable? Only to the extent that they can are subsequently supported or refuted by other independent lines of inference.So with respect to macro-evolution of higher taxa, there is perhaps no definitive testability at this time. But we sure have the tools to accumulate a lot of independent lines of evidence that, in many case, converge on a 'most likely' phylogeny for particular groups. It's the best existing procedure for approximating actual cladistic relationships.I know that many creationists would like to 'retreat' to a defense of creation acting only at higher level taxa, but that is still a cop-out. Molecular biology is rapidly quantifying degrees of relatedness among families and orders. At the level of primary biological enzymes, for example, even we humans we don't look that much different from some bacteria.

Well if it isn't useful for classifying forms of life, what is it good for? I wasn't aware that 'relatedness' could 'state' anything,
but it certainly implies linkage between living things, by definition.You might interpret the similarities as pointing to a common creator, but science has developed various means for quantifying these similarities (and differences) to come up with objectively determined DEGREES of relatedness. Now that is actually useful - you can now say that organism A is more related to B than to C. So we are no more related to monkey kind than we are to 'algae kind'
or 'bacteria kind'? I am sure we all have some very similar enzymes and other proteins in common, but the number of differences are few between man and monkeys. In fact "Studies indicate that humans and chimps are between 95 and 98.5 percent genetically identical."
So similar, in fact, we probably belong in the same Genus.See:
Chimps Belong on Human Branch of Family Tree, Study SaysYou need to read more outside of your Sunday school assignments.

Good one Mick.Now let me see, which of these animals can we use as the 'outgroup' for this little exercise in phylogenetic inference. ?I wonder.......To be fair, I guess we better make sure that old eclipse here knows what an outgroup is..."The distinction between rooted and unrooted trees is very important, but it is also often problematical for non-experts. ...the most common method of cladistic analysis (particularly for sequence data) involves producing an unrooted tree and then rooting the tree using the outgroup. This rooting of the tree then indicates the direction of evolutionary change on the cladogram; and this allows hypotheses of relative character-state polarity (ancestral versus derived) to be produced..."See complete article here:http://www.sasb.org.au/TreeBuild/TreeBuilding3.htmlLet me simplify.Without identifying an obviously dissimilar (= obviously unrelated) organism, relative to the group for which you wish to determine cladistic relationships, you cannot determine degrees of relatedness among the obviously similar organisms within that group.All 'good' phylogenetic trees are 'rooted' in a common ancestor, but in the case of the 'outgroup' selected for a particular analysis, the exact identity of this common ancestor doesn't really matter for the purpose. It is just a reference point that permits mathematical determination of how far each of the other organisms (taxa) have diverged from one another over time.Just my long winded way of saying that Mick's 'outgroup' is obviously the pygmy hippo - only distantly related to pigs at the Order level, Artiodactyla, I believe. Most of the pigs depicted belong to the same species (varying in morphological traits only as a result of selective breeding by humans) and all the peccaries to the same Old-World Genus, Sus, within the family Suidae.

Fabulous Pigs !
Ya gotta love 'em.PS: I was just guessing about the peccaries.
What is the current consensus on their relatedness to the genus Sus ?

So before we deal with the specifics, lets look at the pattern of reasoning here.Apparently anyone would be wasting their time trying to convince you otherwise because you have already made up your mind !?I ask you then, why do you waste *your* time entering into this debate in the first place?Do you want to avail yourself of an opportunity to preach and, at the same time, avoid the opportunity to actually consider other cogent analyses? Some of us might argue that that has already occurred in a number of cases....
Besides, if your argument is older documents are more reliable, would you rather have a surgeon use a 19th century manual or a 20th century manual when he operates on you ? Actually, Columbus was no where close to the first person to hypothesize a spherical earth. It has to go back to Ptolemy or earlier. Someone help me out here.But I would like to know where in the Bible it says that the earth is round ?
Doesn't sound familiar.You bear the burden of proof - provide us with a 'chapter and verse'.This message has been edited by EZscience, 05-04-2005 10:17 PMThis message has been edited by EZscience, 05-04-2005 10:19 PMThis message has been edited by EZscience, 05-04-2005 10:21 PM

Mick :
Thanks for straightening me out.
I'm not good with vertebrates

Schrafinator, I honestly hope you get to teach political science.
I couldn't have said it better.

I would address these protestations, but I think Schrafinator has already given you more than you can handle. Schrafinator: It looks like an ocelot 'kind' of cat to me.
I would like to see eclipse try and keep one as a house cat,
just because it sure 'looks like' one.As far as evidence of speciation in progress, that was my point in starting this whole thread. There is now plenty of evidence. Other good examples are given in posts 1, 2 and 11.This message has been edited by EZscience, 05-05-2005 07:36 AM

OK. You are the Cat expert.Still, it kind of looks like an ocelot 'kind' of cat, so maybe eclipse doesn't need any further clarification. Of course, that's not quite going to cut it for the rest of us.
Inquiring minds want to know the actual species....Is your cat then a 'fishing cat', Prionailurus viverrinus ?This message has been edited by EZscience, 05-05-2005 02:35 PM