beth

I need some good evolution arguement so that I can come back at a fundie.

He poses questions such as," Why do we not see any species that are in the process of evolving into other species." I am not too bright in this area and I said that it is supposed that a new species, or man, for that matter, was a species born from another. I told him in the case of man, he was better adapted to survive than his ansestors...I got ridiculed and told that evolution is BS.

So my question is, why don't we see species that are macro evolving? Oh, here's a site that basically explains the arguments that are posed to me. Creationist site.

Or are there examples today of macro evolution?

pz

All species are continually in the process of evolving, so his comment really makes no sense.

If you want to argue the fact of macroevolution, you ought to get down to the library or book store and pick up Carl Zimmer's At the Water's Edge. It's a very readable book that describes the events and mechanisms behind tetrapod and cetacean macroevolution.

Oolon Colluphid

Hi blondegoddess!
Observed instances of speciation
Sort of. At the time, there would be little to distinguish the incipient new species from its parent one. Speciation is all about the evolution of isolating mechanisms. See here, and especially this bit of it.

The point being, ‘macroevolution’ (see this forum passim ) is (mostly) accumulated ‘microevolution’.
Adaptation is always, crucially, relative, to the environment, the circumstances, of the population. (Bear in mind that it’s populations that evolve, not individuals.) So yes, you’re right, but it’s to do with the circumstances of one lineage -- leading to us -- being different from that which led to chimpanzees... or aardvarks, or cobras, or willow trees.
Don’t worry. They don’t know what they’re talking about.
Because that’s not how evolution works, and so they are attacking a straw man.

But you could try showing the power of selection by pointing out that we have evolved chihuahuas from wolves in just a few thousand years. (The selection being artificial matters not a jot: as far as the genes that make the bodies are concerned, some made it into the next generation, others didn’t. In an environment containing human aesthetics, some were better adapted than others. So it was only those that left descendants.)
Ah, I see they talk about dogs. Well, get them to define ‘kind’ (that’s always a fun one!). Since speciation is observed (as most creationists accept), we need to know in order to tell if they really are immutable. What are the barriers that prevent one becoming a different one?

If and when you get an answer, bring it back here, and we’ll show why their definition doesn’t work.

Since they’ve mentioned humans, I’m afraid, folks, that I’ve no alternative but to post this pic yet again:



Ask them which are the apes, and which are the humans
No, for the reasons above.

Hope that helps.

Cheers, Oolon

KC

First of all, there are numerous examples of observed speciation:

Observed Speciation

As for the link you provided:


This is a misrepresentation of evolution. A moment's reflection will tell anyone this, since evolution deals with extinction as well as adaptation.


Blyth saw natural selection as a conservative force, which preserved what he saw as typical species 'norms' (and which he never demonstrated as actually existing). This is NOT what Darwin or Wallace envisioned, since they saw NS as a creative force that preserved the best adapted variations, and acted in a cumulative way to bring about changes in populations. This kind of NS has been observed and documented.

A moments reflection should tell you that this statement is absurd. If true, then the representative pairs on the ark would have to possess ENORMOUS amounts of variation in their genomes, since we know that mutations alone could not account for the varieties we see in teh time frame of only ~4500 years since the Flood. We would then have to assume that natural selection sorted out all of that variation into the diversity of life we see in that time. There is no evidence for that.

[quote]"The central question of the Chicago conference was whether the mechanisms underlying micro-evolution can be extrapolated to explain the phenomena of macro-evolution. At the risk of doing violence to the positions of some of the people at the meeting, the answer can be given as a clear, No."
- Quote from Evolutionist Roger Lewin admitting that variation occurs, but that variation does not cause evolution. Quote from "Science" vol. 210, Nov 21, 1980 pg. 883 (source RQB). [quote]

We know that populations diverge from each other genetically over time. Its a fact, contrary to what the site says about Lewin's remarks. Macroevolution remains a relative term, indicating the degree of divergence of lineages. The longer the time since the divergence, the greater the differences between the lineages. Extinction of more intermediate forms enhances the observed differences between groups. There is no magic barrier to macroevolution.

Rather typical creationist hyperbole, I'm afraid. Evolution claims nothing of the sort.

A rather liberal interpretation of scripture.

KC

gravitybow

Quote posted by KC, from the Creationist site blondegoddess links to:

Another fine example of quote mining in the service of the creationist lie. Roger Lewin "admitting" that "variation does not cause evolution?" No way!

Here is a link to the entire article, "Evolutionary Theory Under Fire" that Lewin wrote. The Chicago conference was all about Punctuated Equilibrium's challenge (rapid changes with long periods of stasis) to the dominance of the Modern Synthesis (gradual, steady changes over time).

First off, here's the complete paragraph:

Where’s the knockout punch to variation? If anything, by advocating Punctuated Equilibrium, Lewin would be saying that rapid variation, not the conventional steady variation, is responsible for macroevolution, quite the opposite of the conclusive “Quote from Evolutionist Roger Lewin admitting that variation occurs, but that variation does not cause evolution” shoehorned into the creationist’s citation! In fact, Lewin includes the following diagram in the article to illustrate his point:


Caption - The classical view is of gradual change (left); more abrupt speciation (right) may instead be the major process. The graphs are drawn as frequency distributions of morphological structure. [Adapted from South African Journal of Science 76, 61 (1980)]

As you can see, variation is present in both models. The graph on the left shows slow variations due to genetic drift over time to create distinct species: macroevolution due to microevolution. The graph on the right shows rapid variations in a brief period (small overlapping bell curves at the branching point) followed by long periods of stasis for species: macroevolution due to some mechanism other than microevolution. Microevolution is still at work in this "continuum with a notable overlap" (chopped off of Lewin’s original quote) , but not as the cause of macroevolution. The difference, then, is that both theories of evolution are based on differing rates and mechanisms of variation. The role of microevolution is questioned, not variation. The bell curves still overlap in both graphs. There is no break (what a creationist would call a created "kind").

Someone lied to make Lewin say that variation does not cause evolution when he says just the opposite. This is typical of the dishonest scholarship that passes for science in creationist circles.

How about this scientific assessment of the situation: "Liar, liar, pants on fire!"

No?

OK, how about this: Show your fundie friend "Evolutionary Theory Under Fire" and have him point where Roger Lewin says variation doesn't cause evolution. As I've already shown, microevolution and variation are not the same thing, although the site you linked to equivocates the two. Point to the graphs Lewin provides and have him show you where variation is absent (non-overlapping). Of course if he reads the entire article, there's always the chance that he'll see how Lewin's work was misrepresented, and you won't have to do anything.

Doubting Didymus

I do this all the time, and I'm really not meaning to be pedantic, but I'm going to have to ask what the creationist in question means by macroevolution. I can't see that we can answer meaningfully if we aren't sure what his objections are. It's possible he means anagenesis (the origin of a new species without a division, as opposed to cladogenesis, the population-division 'speciation' that is so easy to demonstrate, but is so rarely impressive to creationists), or its possible he means common descent, which is easily the least tricky thing to prove when we have good fossil record examples, serial homology, and the king-hitting endogenous retroviruses on our side. He might mean "large - scale morphological change" (monkeys to humans, for example). It's also unfortunately possible that he means "moving from one kind or higher level taxonomic group into another". If so, there is nothing for it but to encourage that the person to actually learn something about the topic (that topic being "biology").

I suspect your best bet is the retroviral insertions, which are unquestionable proof of common descent. The idea is that we have sections of DNA inserted into our genomes, which we can identify as viral in origin, which are also present in exactly the same pattern, and exactly the same places in apes. The only sensible interpretation is that both apes and humans got the fragments from a common ancestor.

This thread is a very readable write-up of the topic by Winace, adapted largely from This Talkorigins FAQ.

MrDarwin

In a nutshell, we can't recognize "macroevolution" until it has already occurred. With any species alive today, we have no idea what it might possibly evolve into in the future. But I would suggest that seals, sea lions, and otters are on the way to evolving into fully aquatic mammals; they just aren't as far along the way as whales. Penguins too, maybe; unfortunately they have never figured out how to bear live young, and thus need to return to dry land to breed. And flying squirrels might very well be in the process of evolving into winged creatures capable of true flight. Fast forward a few million years, and we'll know for sure.

But if by "macroevolution" you simply mean the evolution of one species into another, only slightly different, species there are plenty of examples. Among animals, species can frequently be classified into two or more subspecies that are geographically separated or overlap at some point and interbreed. There are many similar examples among plant species. These subspecies may be very similar, or very different. In some cases, hybrids between the two populations have reduced fertility. Eliminate that overlap and let the two subspecies diverge a bit more and bingo, you've got two species.

Another pattern I see with the plants I work with is that a genus often consists of several species, with one or two or a few widespread and morphologically variable species, and several morphologically well-defined species with restricted distributions that have obviously evolved from one of the widely distributed, variable species. Variation precedes speciation; speciation merely enforces the differences between related populations.

The fact that species are not static and give rise to new species makes classification extremely difficult because there are many taxa at various stages of speciation, from slightly separated and barely distinguishable populations, to widely separated and very different populations that are clearly separate species, with every step along the way represented.

beth

Well, considering that I am not too scientic-minded and I don't know many of the terms, I shall try to explain in ignorant lay-man's terms.

First off, I want to thank everyone for their replys and for the links. I also want to thank all who explained the evolutionary process to me. I have a better understanding and I think that I will be able to argue whenever need be.

The questions I get are things such as,"If God didn't create things, why do we have viruses, where do they come from?"

"Where do dogs come from? Oh that's right, they evolved from the dinosaurs." When I explain that they evolved from wolves, the reply was, "Then how did a new species get born from a wolf and why don't e see it today?"

I also get questioned on how the apes evolved into us. I am basically dealing with a full-fledged creationist. It wouldn't matter much to me, but now that I am not a creationist, I am constantly being drilled wth stupid questions about evolution. But I think I have enough info to at least come back with educated answers. Thanks.

Peez

Hi blondegoddess,

Here is another way of looking at it. I show you a photograph of several people cycling along a rural road between city A and city B. You cannot tell from this photo just how far they have travelled, or how far they will continue to travel. If we think of "micro-evolution" as cycling a short distance, say from city A to a farm just outside, and "macro-evolution" as cycling a long distance, say from city A to city B, then it is clear that we cannot distinguish "macro-evolution" from "micro-evolution" simply by looking at a population as it is today.

Peez

P.S.: Don't expect the creationist to be immediately convinced.Jonathan Swift

That being said, you might plant the seeds that eventually help them to shed their chains of ignorance.

MrDarwin

A bit off-topic, but I've been thinking about the differences between whales--which are fully aquatic--and other creatures like seals, sea lions, and otters which have to return to land to breed. This is a major obstacle to becoming truly aquatic, which penguins will likely never overcome (as no birds have ever gotten around laying eggs) and which seals, sea lions, and otters have not yet managed to overcome. Why not? Then I got to wondering how whales got around this obstacle: clearly they need to have babies that are well-developed and capable of swimming immediately upon birth, and perhaps this was a characteristic of their terrestrial ancestors, rather than something they had to evolve in the process of becoming aquatic animals.

And then it struck me: whales are ungulates. One characteristic of ungulates is that many (most?) have babies that are capable of standing and walking (and presumably swimming, in amphibious intermediates) within minutes of birth. Seals, sea lions, and otters, on the other hand, are carnivores. One characteristic of carnivores is that they have babies that are quite helpless for several days or even weeks after birth. So there you have it: the land-living ungulate ancestors of whales were pre-adapted to giving birth without having to return to land. Most other amphibious mammals are stuck halfway, because they give birth to helpless babies that are incapable of swimming.

This may explain how manatees and dugongs were able to become fully aquatic: their closest relatives are elephants, which also have well-developed, mobile young. It may also explain why so many different lineages of reptiles were able to become aquatic in the Mesozoic, as many reptiles bear live young and most have babies that can fend for themselves immediately upon birth.