Re: "Columbus Theory" was Monarchs and Monoculture in southern Michigan

Tim and all

I don't have a firm decision on the "Columbus Theory". I Would like to add to the debate two more pieces of information.

Quoting Alex Netherton:
"Deforestation was rampant in the eastern US from about 1670 on. Clearing
land for farms in the 18th century wiped out a lot of unspoiled forests,
and the timber boom of the late 1800's and early 1900's pretty much
chewed up all the old growth forest. I have seen photos of denuded
mountains taken in this area in the 1920's. (Western North Carolina)
This was true of most of the Appalachians and most of the Eastern US;
after the timber "harvest" (call it rape) and the resulting "slash"
(waste branches, leaves, small trees), much of the Southern Appalachians
burned with a great fire in 1919, in many places scorching the ground
over a foot deep. I can take you to a place on the Blue Ridge Parkway
where this happened. Though a lovely place, no trees grow on it, and it
is called "Graveyard Fields". In 1900 it was a great forest."

Quoting Phil Schappert:
"Land use changes in Ontario and most southern regions of Canada over the last 200 years have likely served to increase the range of Milkweeds, especially those species such as A. syriaca and A. speciosa which grow in open situations. There is no doubt that Monarch ranges have increased over the last 50 years. Urquhart & Urquhart (1979a) give the breeding range of the Monarch in Ontario during the years 1937-1940 as Kingston to Goderich (approx. 44° N) and south with low numbers breeding in Barrie and Midland to the north. By 1975 they found that the Monarch was commonly breeding along the north shore of Lake Huron from Sudbury to Sault Ste. Marie (47° N) and in Thunder Bay and that in 1977 Monarchs were considerably more common at Sault Ste. Marie than they were at Toronto (Urquhart & Urquhart 1979a). Similarly Urquhart & Urquhart (1979a) reported no breeding in B.C. or Alberta with only scattered larvae recorded through Saskatchewan and Manitoba in the 1940-44 period. More recent records show that breeding does occur in B.C. and Alberta (C. Guppy, pers. comm.; Bird et al. 1995) and that they are now more common in Saskatchewan and Manitoba (Hooper 1973; Klassen et al. 1989). This recent range expansion may slow somewhat but is expected to continue."

Ed Reinertsen


----- Original Message ----- From: "Tim Nash" <tim.nash@xxxxxxxxxx>
To: <ereinertsen@xxxxxxxxxxx>
Cc: <fnkwp@xxxxxxx>; <LEPS-L@xxxxxxxxxxxxxx>
Sent: Sunday, August 28, 2005 5:46 AM
Subject: Re: "Columbus Theory" was Monarchs and Monoculture in southern Michigan


Ed

Can we also move away from the " Columbus Hypothesis" as there are better explanations of the known facts? You may remember the email exchange 2 years ago on TILS which I have copied below.
Best
Tim

On 27 Aug 2005, at 14:54, Ed Reinertsen wrote:


Ken,

An excellent and new discussion topic. Thanks for
bringing up, and with some grace turning a negative
discussion in a more positive and productive
direction.
Ed Reinertsen


----- Original Message ----- From: "Kenelm W Philip" <fnkwp@xxxxxxx>
To: <LEPS-L@xxxxxxxxxxxxxx>
Sent: Saturday, August 27, 2005 5:03 AM
Subject: Re: Monarchs and Monoculture in southern Michigan




Neil responded to my query with:


The data cannot be relied upon to provide the results you are  looking
for because there aren't enough of them.


First, I have no ax to grind here--and am not looking for any  results.
I was merely asking how Neil's comment about tag recovery being
determined by local weather at the overwintering sites had any
relevance to the problem at hand, which concerned the ratio of  eastern
to mid- western tags. That question he did not answer.
I agree that the numbers Paul found and reported are small, and make
firm conclusions about trends hard to support. There are, however,
clearly more midwestern than eastern recoveries (subject to change
when all the data are in).
As to whether GM crops are harmful or harmless to butterflies (or to
other organisms--they are certainly as hard on weeds as they are
designed to be!)--that depends on the specific organism, and also
requires one to take a long view of the situation. Is the number of
milkweed plants in the midwest before the advent of GM crops larger
or smaller than the number before Europeans came to the New World? Is
the _current_ number larger or smaller? Are the masses of Monarchs in
the midwest an old event. or something of recent origin due to agri-
culture? I have no idea, but the Monarch researchers may know some-
thing about this.


You know Ken up there in Alaska you don't seem to understand what
modern agriculture is doing to butterfly populations.


Well, although that kind of thing is not a major problem in Alaska, I
_do_ read, and have visited the lower 48 states a number of times
since I moved to Fairbanks. I recall reading about the effect that loss
of the hedgerows had on English butterflies, for example... But what
I would like to see are data on the abundance of milkweed in the mid-
west through history. Is the pattern of weedkiller spraying in GM crops
allowing significant amounts of milkweed to survive? Is that amount,
whatever it may be, larger or smaller than the amount present before
the introduction of large-scale farming?
Similar questions would arise for any butterfly foodplant in the
midwest.
Ken Philip
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(Post below, in black by Tim Nash, in blue by the late Ron Gatrelle)
On Saturday, November 29, 2003, at 01:25 PM, TILS-leps-
talk@xxxxxxxxxxxxxxx wrote:



Lack of human records only means that humans were not aware of something.

My problem is that the time of human notation of a natural phenomenon
should not be taken to mean that that phenomenon did not exist before
humans realized that it existed. For 30 + years here on the South
Carolina coast there has been (and is) nothing to indicate a migration of
Monarchs. I don't think that anyone back in 1800 living in the eastern
United States would have noted a "migration" and even if they saw a group
of Monarchs roosting or flying they would not have put 2 + 2 together and
concluded migration.



However it is reasonable to say that any such migrations were small compared to those now.

Naturalists who then travelled to the USA would have had 'letters of introduction' to officials and useful contacts, who would have suggested other useful people to talk to. When you had to travel inland by foot and/or horse, asking the locals saved a lot of time. However there was no mention of the migrations.

If large migrations took place on the plains, occasionally or annually, they would have entered the oral histories of the Plains Indians. These were close observers of nature, as their lives depended on it. Yet again no such mention.



Let's also consider at what point in modern history did the scientific
community discover the Mexican overwintering site phenomenon. Are we to
assume that because no one was aware of this that it therefore did not
exist till we became aware of it. There were no bacteria before Pasteur.
The world was not round before Columbus. No electricity. No gravity.
For anyone to suggest that the Monarch migration phenomenon has not existed
for thousands of years is frankly... well, one can put in their own term.




The Monarch migration phenomenon is easily observed by the naked eye.

Given an abundant food source, it wouldn't have taken many years for a few successful migrators to reach large numbers. Indeed the reason that few Mexican overwintering sites are used (out of many that seem suitable) may be that the migrating population grew very quickly from these few and that the migration hasn't been going for a long time in the current form.




What is reasonable, is to calculate the likely abundance or scarcity of
Milkweed pre European arrival and then to _project_ the corresponding
numbers of Monarchs and "normal" size of those migrations. It is possible
the population of Monarchs was relatively small and the migrations, and
numbers in Mexico only a fragment of what it is today. Comments ????



The best way of solving this question is, as Jorge suggested, a pollen analysis.


(Post in black below by Tim  Nash)

Following up yesterday's post, an initial hypothesis is:

Milkweed establishes itself fairly quickly in disturbed soil. In the aftermath of the Civil War, when the US was still largely an agricultural society, freeing of the slaves and the casualties among the farmers and farm labourers in the armies of both sides led to abandoned and less well weeded fields. Milkweed became much more widespread. The westward expansion of agriculture into the Great Plains with family farms allowed Milkweed to spread further.

So, under this hypothesis, migration is a recent natural response to a widespread food source being available in the warmer months to the north of the Monarch's normal range.Also, if the Monarch develops a successful overwintering strategy migration will probably die out naturally.

Begin forwarded message:



From: Tim Nash <tim.nash@xxxxxxxxxx>
Date: Fri Nov 28, 2003  03:53:47 PM Europe/Paris
To: TILS-leps-talk@xxxxxxxxxxxxxxx, Norbert Kondla <colias@xxxxxxx>
Subject: Re: Doubts on the Columbus Hypothesis

Rather than destruction of the forest, has anyone looked into much more widespread tilling of the soil as a prime cause for the spread of Milkweed and hence the Monarch? The opening of the plains to agriculture in the mid 19th century would then tie up with the lack of records for migration before 1865.

Even with modern estimates of 20 million native Americans at the time of Columbus, much of the USA was covered with hunter/gatherer populations. Only in areas like the Mississippi basin was intensive agriculture widespread.

Tim Nash
On Friday, November 28, 2003, at 02:05 PM, TILS-leps-
talk@xxxxxxxxxxxxxxx wrote:



  Date: Thu, 27 Nov 2003 10:53:33 -0800
   From: Norbert Kondla <colias@xxxxxxx>
Subject: FW: Doubts on the Columbus Hypothesis

Furthermore re below I doubt that Europeans destroyed much of the forest
that covered North America. Although I don't have the citations handy I
do recall seeing literature on this subject a number of times over the
years. Some native Americans frequently burned forests. That plus
natural fires suggests that the forests actually present upon European
arrival may not have been nearly as widespread as commonly thought. Also
I guess it depends on what one means by the word forest. A forest is
more than just a bunch of trees growing in a place at a given point in
time, at least to me. My understanding is that in portions of the
eastern USA there was conversion of lands, that would naturally be
forested for much of the time, to agriculture and settlement but that
over time some of these lands have been subjected to different use
tenures and what was for a long time agricultural land has again
reverted to forest. What the net loss/gain of forested lands has been is
unknown to me and it would certainly vary with the particular year that
one used as the base amount of forested land and would certainly vary
every year between now and 'way back then'.

-----Original Message-----
From: Ed Reinertsen [mailto:ereinertsen@xxxxxxxxxxx]
Sent: Thursday, November 27, 2003 9:58 AM
To: Ron Gatrelle; TILS talk; Leplist; Southwest Leps; moth-rah
Subject: [leps-talk] Doubts on the Columbus Hypothesis

I don't think the Columbus Theory is a valid explanation for the
start/reason of the migration of the North American Danaus plexippus
(monarch).
Native Americans were using Asclepias (milkweed) for medicine and other
things long before the arrival of European
colonists. This leads me to beleive there was sufficant Milkweed for the
Monarchs.
According to this theory, the North American population has not always
migrated, but began doing so after the arrival of European colonists.
The
Europeans destroyed much of the forest that covered North America, and
was
replaced by milkweed.





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