The chaos theory of evolution

[alfredo]

Looks like climate change may not push evolution.

http://www.newscientist.com/article/mg20827821.000-the-chaos-theory-of-evolution.html

IN 1856, geologist Charles Lyell wrote to Charles Darwin with a question about fossils. Puzzled by types of mollusc that abruptly disappeared from the British fossil record, apparently in response to a glaciation, only to reappear 2 million years later completely unchanged, he asked of Darwin: "Be so good as to explain all this in your next letter." Darwin never did.

To this day Lyell's question has never received an adequate answer. I believe that is because there isn't one. Because of the way evolution works, it is impossible to predict how a given species will respond to environmental change.

[MineralMan]

1. Lyell's question doesn't really deserve a serious answer.

Glaciation may eliminate a species in a specific region, while it continues to thrive in less affected areas. When the climatic conditions return to a more normal, the range of that species expands back into the previously uninhabitable region. 2 million years is nothing for mollusks.

Here in Minnesota, we're seeing that phenomenon in reverse. Yesterday, my wife saw a couple of Summer Tanagers at her mother's bird feeder. At one time, they were exceedingly rare here, but as many other species have done, they have expanded their range as the climate has warmed slightly. Other species, like opossums and raccoons, along with coyotes, which were seldom sighted in Minnesota, are not commonplace as well. And that's just in a decade or two.

Mollusks take a long time to spread back into a region. They don't migrate far, but they do spread as conditions change.

There was a lot people, even scientists, didn't know in 1856.

[alfredo]

2. I've been noticing a wasp I've never seen in this area. I do

a lot of Macro photography, so I am very aware of "creepy crawlies."

[Enthusiast]

4. Good post.

Back then fossilization wasn't widely understood. Even today many people are under the impression that the fossil record is complete while nothing could be further from the truth. In Ohio, where I live, the fauna of the Carboniferous and earlier is well represented, yet, because Ohio was a highland during the Mesozoic, there are no fossils or strata representing this period. Such is the nature of the fossil record.

[alfredo]

5. I live in the Bluegrass region of Ky, we are Ordovician because

all the newer strata has been hauled away. Flexicalymene is our mascot. We see a lot of Isotelus fragments, crinoid up in Bourbon County, and Mollusks of all sorts.

Check out the Falls of Ohio north of Louisville to see the largest exposed Devonian fossil beds.

http://www.fallsoftheohio.org/

I used to fish down there. Great place to find channel cats. Never got over to the far side. The line of trees bottom right has some small caves were hobos used to sleep.

[Enthusiast]

12. Thanks for pointing this out!

It looks like a smallmouth bass hideout. I would like to have seen it in the original state, before the water was raised.

[alfredo]

13. There was a rapids that covered it. When the wickets are

open kayakers ride the eddies.

[HereSince1628]

3. A priori, I am not troubled by this. Veligers are vagile.

Local, even regional populations can be extirpated and later populations can recolonize. Look at the planet...life disperses.

Without knowing anymore about the paleo-biogeographical issues of this problem, I'd breeze by it without raising an eyebrow.

[alfredo]

6. I guess he never thought of repopulation.

BTW, 1628 is as far back as we have traced our name in West Prussia. We migrated out of Armenia maybe as early as the 1000's.

[HereSince1628]

7. My surname is a place name from SE of Berlin

The origins of the name are unclear, but it was used in Brandenburg at least 3 times and for the place northwest of Lubbenau identified by my paternal great grandfather as his origin the name goes back to at least the 1300's. Maybe we share some gene variants. Do you ever have an inexplicable urge to stare at storks, punt a boat or to eat carp?

The Sayre side of my family, which is linked to crazy but wonderful Zelda Sayre Fitzgerald goes back to Southampton, Long Island. We were just nuts that came to this continent, and we're still producing nuts like me.

BTW in the mid 1800's larvae of marine invertebrates were poorly known. It was pretty common to misplace larvae and be unable to link them to their adult forms.

[alfredo]

8. We have found an area in Northern Iran with our surname. At one time Armenia

Controlled parts of present day Iran.

Culturally I am German. I like cabbage with my shish kabob. Brats and hummus are another favorite.

Dark haired girls that can polka are a turn on.

Still our migrations could also reflect the chaotic nature mutations in our DNA. Why did we go west instead of east? There is mention of a Siberian Tarter with our Surname. Of course Tartar was a catchall name for people of the near east. He had a Muslim given name.

[HereSince1628]

9. The culinary masterpiece of Lustasia is the dill pickle

My grandma served cukes, raw or pickled, with everthing, including carp!

[alfredo]

10. I was raised in a very German community.

Those pioneer Germans were smart enough to not run the rapids at the falls of the Ohio, settling down in Louisville.

Again chance played into migration.

[alfredo]

11. My dad spoke German as a kid. In school he would cuss out

the teacher in German until he got a teacher that could speak German. He said she "beat the German" out of him. He still swore in German, but not at teachers.