"Columbus Theory" was Monarchs and Monoculture in southern Michigan
tim.nash at wanadoo.fr
Sun Aug 28 06:46:52 EDT 2005
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.
On 27 Aug 2005, at 14:54, Ed Reinertsen wrote:
> An excellent and new discussion topic. Thanks for
> bringing up, and with some grace turning a negative
> discussion in a more positive and productive
> Ed Reinertsen
> ----- Original Message ----- From: "Kenelm W Philip" <fnkwp at uaf.edu>
> To: <LEPS-L at lists.yale.edu>
> 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
>>> for because there aren't enough of them.
>> First, I have no ax to grind here--and am not looking for any
>> 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
>> 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
>> 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
>> 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
>> 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 at yahoogroups.com wrote:
> Lack of human records only means that humans were not aware of
> 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
> United States would have noted a "migration" and even if they saw a
> 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
> The world was not round before Columbus. No electricity. No
> For anyone to suggest that the Monarch migration phenomenon has not
> for thousands of years is frankly... well, one can put in their own
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
> the population of Monarchs was relatively small and the migrations,
> numbers in Mexico only a fragment of what it is today. Comments ????
The best way of solving this question is, as Jorge suggested, a
(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
Begin forwarded message:
> From: Tim Nash <tim.nash at wanadoo.fr>
> Date: Fri Nov 28, 2003 03:53:47 PM Europe/Paris
> To: TILS-leps-talk at yahoogroups.com, Norbert Kondla <colias at shaw.ca>
> 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 at yahoogroups.com wrote:
>> Date: Thu, 27 Nov 2003 10:53:33 -0800
>> From: Norbert Kondla <colias at shaw.ca>
>> Subject: FW: Doubts on the Columbus Hypothesis
>> Furthermore re below I doubt that Europeans destroyed much of the
>> 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
>> years. Some native Americans frequently burned forests. That plus
>> natural fires suggests that the forests actually present upon
>> 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
>> 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 at iprimus.com]
>> 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
>> Native Americans were using Asclepias (milkweed) for medicine and
>> things long before the arrival of European
>> colonists. This leads me to beleive there was sufficant Milkweed
>> for the
>> According to this theory, the North American population has not
>> migrated, but began doing so after the arrival of European colonists.
>> Europeans destroyed much of the forest that covered North America,
>> replaced by milkweed.
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