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Jens
2010-Sep-21, 06:35 AM
This seems like just the kind of topic that BAUT experts might be able to answer or at least be interested in. I've heard before that there were no earthworms in North America before the European colonization. This paper (http://www.dnr.state.mn.us/invasives/terrestrialanimals/earthworms/index.html)seems to confirm it, and seems written by people with credentials. However, the Straight Dope appears to disagree (http://www.straightdope.com/columns/read/1916/whats-the-story-on-north-american-earthworms). And reading this story (http://www.sciencedaily.com/releases/2008/10/081027152119.htm) from Science Daily seems to give what might be an answer: maybe there weren't many earthworms, and they were not the same type, so the ecology was in fact changed by European imports.

Anybody know a lot about this?

Trakar
2010-Sep-21, 06:58 AM
This seems like just the kind of topic that BAUT experts might be able to answer or at least be interested in. I've heard before that there were no earthworms in North America before the European colonization. This paper (http://www.dnr.state.mn.us/invasives/terrestrialanimals/earthworms/index.html)seems to confirm it, and seems written by people with credentials. However, the Straight Dope appears to disagree (http://www.straightdope.com/columns/read/1916/whats-the-story-on-north-american-earthworms). And reading this story (http://www.sciencedaily.com/releases/2008/10/081027152119.htm) from Science Daily seems to give what might be an answer: maybe there weren't many earthworms, and they were not the same type, so the ecology was in fact changed by European imports.

Anybody know a lot about this?

"Foriegn Worm Alert" - http://www.smithsonianmag.com/science-nature/phenom_aug00.html


...Earthworm taxonomist Sam James, a professor at Iowa's Maharishi University of Management, says that until the arrival of European colonists, the continent above the glacial line was worm-free. "When ice sheets covered much of northern North America," he says, "native earthworms were eradicated." The glacial edge runs from Washington State to Long Island, with a southerly dip below the Great Lakes and Ohio.

Although native earthworms are found below this line, the innocuous locals, which number 90 or so identified species, still haven't squirmed more than 100 miles north in thousands of years. The invaders came to this continent packed in the soil around potted plants, in ships' ballast or tucked in the hooves of livestock. Aided by their fevered reproductive rate, the official blessing of the U.S. Department of Agriculture and a reputation for results and durability with fishermen, they prospered.

Still, until the past couple of decades, exotic duff-gorging worms were apparently uncommon in undisturbed forest areas. Back in the 1960s worm expert Gordon Gates (considered by at least one biologist to be the "greatest oligochaetologist who ever lived") was the first to suggest that exotic earthworms were arriving in forests with fishermen who liberated their unused bait....

And here's a clear example of one rather spectacular native species - http://people.oregonstate.edu/~rosenbed/earthworm.html

Swift
2010-Sep-21, 01:21 PM
<snip>
... maybe there weren't many earthworms, and they were not the same type, so the ecology was in fact changed by European imports.
Short answer, the quoted part above is the situation.

jlhredshift
2010-Sep-21, 01:35 PM
Interesting, so the oak trees outran the worms as the ice receded.

Swift
2010-Sep-21, 02:31 PM
Interesting, so the oak trees outran the worms as the ice receded.
I suspect it relates to the travel modes of oak seeds versus worm "seeds".

jlhredshift
2010-Sep-21, 02:35 PM
I suspect it relates to the travel modes of oak seeds versus worm "seeds".

Probably so, squirrels don't fish.

Ara Pacis
2010-Sep-21, 08:58 PM
Interesting, so the oak trees outran the worms as the ice receded.

Entings, of course. I guess this disproves the maxim that the acorn doesn't fall far from the tree.

jlhredshift
2010-Sep-21, 09:30 PM
Entings, of course. I guess this disproves the maxim that the acorn doesn't fall far from the tree.

Well, let's see. I have an isolated oak south of the house and I just went and looked and found acorns easily twenty feet from the trunk. Let's say twenty feet every twenty years and in a thousand years you have a thousand feet. On the other hand there are younger oaks scattered around the property about every five hundred feet into our woods and I assume they were squirrel assisted and a guess estimate is that they are twenty years younger on average. So, five hundred feet every twenty years, so about five miles in a thousand years.

Doesn't sound right, there must be long haul squirrels.

HenrikOlsen
2010-Sep-21, 09:59 PM
Oak tends to be the last tree to enter in the natural temperate grasslands to shrubberies to deciduous forest transformation, after the alders and birches so I'm not really surprised.
It's not a pioneering species.

JustAFriend
2010-Sep-22, 12:28 AM
Doesn't sound right, there must be long haul squirrels.

Dont forget BIRDS....

Ara Pacis
2010-Sep-22, 04:32 AM
And water.

jlhredshift
2010-Sep-22, 11:46 AM
Henrik is correct in stating that oak is not a pioneering species, but it is an indication of deciduous forest environ. Now, I do not know of any bird that is capable of eating acorns, but I guess they could transport them. As to water, yes, but one would assume downstream.

The drainage of the Atlantic coast of North America is generally south or southeast or east. At the archaeology site known as 6lf21 Templeton, in Litchfield county in western Connecticut, red oak and either juniper or white cedar were found associated with Clovis like lithics and radiocarbon dated to 10,190 +- 300 (w-3931) which would be around the tail end of the Younger Dryas (R. W. Moeller; 1980). This site would have been under a glacier 20-22 Kya and the ice receded by 16.5 Kya (J. C. Ridge; 2004). The Shepaug river on which the site is located flows south to the Atlantic. Therefore, people were burning oak on the river bank at the end of the Younger Dryas and though spruce and pine may have dominated, oak from some refugium had made it to western Connecticut in six thousand years; (Moeller, 1980). I can't speak to the presence or absence of worms at the site.

BioSci
2010-Sep-22, 03:22 PM
Now, I do not know of any bird that is capable of eating acorns, but I guess they could transport them.

How about jays. woodpeckers, turkeys, chickadees, quail, grosbeaks, cardinals, grouse, nuthatches, and ducks among others.:whistle:

NEOWatcher
2010-Sep-22, 03:29 PM
What about other animals?
I know there are some seeds and/or situations that can still germinate after passing through a digestive system. Could this be true of acorns?

jlhredshift
2010-Sep-22, 04:00 PM
How about jays. woodpeckers, turkeys, chickadees, quail, grosbeaks, cardinals, grouse, nuthatches, and ducks among others.:whistle:

Ok, now I know.

jlhredshift
2010-Sep-22, 05:10 PM
It is unfortunate that due to the acidic nature of the soils of New England that just as the worms do not fossilize, neither do the bones of birds. I can not determine whether, say corvids, were present in the late Pleistocene forests.

Trakar
2010-Sep-22, 11:23 PM
How about jays. woodpeckers, turkeys, chickadees, quail, grosbeaks, cardinals, grouse, nuthatches, and ducks among others.:whistle:

:think:"Woodpecker"?! isn't that a bit redundant?:confused:

jlhredshift
2010-Sep-23, 01:07 AM
:think:"Woodpecker"?! isn't that a bit redundant?:confused:

Well, I wasn't going to say anything but woodpeckers eat bugs; and a duck eating an acorn?

Swift
2010-Sep-23, 01:45 AM
Well, I wasn't going to say anything but woodpeckers eat bugs; and a duck eating an acorn?
At least one species of woodpecker (the Acorn Woodpecker (http://www.allaboutbirds.org/guide/Acorn_Woodpecker/id)) collects and eats acorns.

The clown-faced Acorn Woodpecker is a common bird of western oak forests. It lives in extended family groups, and all members of the group spend hours and hours storing thousands of acorns in carefully tended holes in trees and telephone poles.

Ducks as a group have very varied diets. Different species tend to specialize in particular types of food, but even a given species may eat lots of different things. (one reference (http://www.hsus.org/wildlife/a_closer_look_at_wildlife/wild_ducks_of_north_america.html))

Most ducks are omnivorous, but some are primarily herbivores and others (such as sea ducks and mergansers) are mostly carnivorous. Plants eaten include those commonly available in wetlands such as seeds, aquatic grasses, and submerged pond weeds. Animals eaten include invertebrates, fish eggs, and fish. Many duck species switch from a diet of mostly plants to a diet of invertebrates just prior to breeding, which may help them acquire sufficient energy for reproduction. Young ducks eat primarily invertebrates.

jlhredshift
2010-Sep-23, 02:25 AM
Thank you; insert the call of Woody the Woodpecker here.

Trakar
2010-Sep-23, 04:50 AM
Well, I wasn't going to say anything but woodpeckers eat bugs; and a duck eating an acorn?

No, it must be true, I've seen ducks stuffed full of acorns,...of course, they were roasted, so I doubt that they consumed them voluntarily!

Trakar
2010-Sep-23, 04:53 AM
Thank you; insert the call of Woody the Woodpecker here.

now that's just overkill

jlhredshift
2010-Sep-23, 12:11 PM
What about other animals?
I know there are some seeds and/or situations that can still germinate after passing through a digestive system. Could this be true of acorns?



Possibly mastodons, caribou, moose, and white tailed deer. However, the mastodonts were gone by +- 10,700 rcybp, the others are still extant.

BioSci
2010-Sep-23, 04:02 PM
What about other animals?
I know there are some seeds and/or situations that can still germinate after passing through a digestive system. Could this be true of acorns?

Although acorns could possibly pass through our digestion system and germinate if swallowed whole, (anyone want to test and report back? :eek:) most acorns eaten for food are chewed or ground up in the process. It is certainly possible that small numbers of acorns may survive if greedily eaten whole by some animals (perhaps wild pigs?), but such a result would not be a significant matter for acorn dispersal and oak trees.

BioSci
2010-Sep-23, 04:07 PM
Well, I wasn't going to say anything but woodpeckers eat bugs; and a duck eating an acorn?

Especially wood ducks (AKA acorn duck) but also other ducks.

eugenek
2010-Sep-23, 04:25 PM
Now, I do not know of any bird that is capable of eating acorns, but I guess they could transport them.

Swallows are known to carry coconuts so I don't see why a migrating swallow couldn't carry an acorn.

jlhredshift
2010-Sep-23, 05:30 PM
Swallows are known to carry coconuts so I don't see why a migrating swallow couldn't carry an acorn.


Especially wood ducks (AKA acorn duck) but also other ducks.



From : Wood Ducks gathering acorns (http://elibrary.unm.edu/sora/NABB/v003n03/p0102-p0102.pdf) (R. L. Briggs)

Jays and ducks, next thing you know it will be sparrows.

Swift
2010-Sep-23, 06:39 PM
Swallows are known to carry coconuts so I don't see why a migrating swallow couldn't carry an acorn.
African or European?

And yes, before anyone asks, you do have to know these things if you want to be moderator
:razz:

NEOWatcher
2010-Sep-23, 07:37 PM
Although acorns could possibly pass through our digestion system...
As an afterthought, what about animals that store thier food, like squirrels. I'm sure that can cause a fairly quick migration of acorns.

jlhredshift
2010-Sep-23, 07:52 PM
As an afterthought, what about animals that store thier food, like squirrels. I'm sure that can cause a fairly quick migration of acorns.

I am sure you are correct.:whistle:

Trakar
2010-Sep-23, 07:53 PM
African or European?

And yes, before anyone asks, you do have to know these things if you want to be moderator
:razz:

Birds with nuts, is that related to chicks with sticks?:think: