I have had a Canadian passport continuously for 50 years. They have seen good use in visits to: Armenia, Brazil, Chile, “Deutschland”, to mention just a few. I received my “Nature” passport, my PhD, in 1973 from the University of Edinburgh, Scotland. I shall use that to guide us on an unusual tour.
Have you ever lost or misplaced your passport? Anxious moments for humans. Do you ever wonder who carries out passport control for Mother Nature? She was here long before “we” put up these artificial borders. Take the Monarch butterfly that flies 7,000km round trip between Mexico and southern Canada, crossing two borders, and taking on average four generations of butterflies to complete the journey in a single year.
About 10 years ago “we” learned that this “record” – humans are great at requiring records – was
beaten by the “Globe skimmer”. Sounds like a racing airplane or sailboat, but is in fact a dragonfly
species that migrates between the subcontinent of India and the continent of Africa – and back covering between 14,000 and 18,000km, also probably in four generations. (“Are we there yet?”)
Passport, please. Yes. We in Carden, the Kawarthas, Simcoe County, can also experience dragonfly migration. There are several species, notably the Green Darner, Variegated Meadowhawk, Wandering and Spot-wing Gliders, and the Black Saddlebag which migrate between here and the Gulf of Mexico.[wc_row][wc_column size=”one-half” position=”first”]
“Take the Monarch butterfly that flies 7,000km round trip between Mexico and southern Canada”[/wc_column][wc_column size=”one-half” position=”last”]
I find it interesting that one of the ways that these migrants are traced is because of an event that
lasted only a couple of minutes approximately 14 billion years ago, during the Big Bang when hydrogen was made from energy. Sometimes an isotope of hydrogen, deuterium, was also created and this can be seen to this day in water. (Perhaps you are aware of “heavy water” used in the Sudbury solar neutrino detector?)
One stage in the life of dragonflies is aquatic when their larvae live in water taking on the “taste”
of deuterium. This amount varies over North America allowing “us” to locate the birth “water” of the
adult dragonflies even when they are found thousands of km away. Fascinating!
But where did that water come from? How did Earth get its water? There are a couple of sources, comets and asteroids. Today we see both groups that have survived 4 billion years of collisions with everything possible in the solar system or even outright ejection from our system. How does their water “taste”? It seems that comets in general tend to have relatively more deuterium than does that of the earth; asteroids today tend to be quite close in “taste” to earth – and dragonflies. However, the picture is not simple enough to allow us to make a definite conclusion. Recently infrared studies have found far more comets beyond the distance to Mars than had been expected, indicating many more comets have been thrown towards earth and also away than had been calculated. And most astronomers do not know about dragonflies, about life on earth and life’s preference, at least today, for water of a certain “taste”. How has life influenced living conditions on earth? Life certainly is responsible for creating an environment that can handle oxygen and free oxygen has been found on comets like the one the Rosetta spacecraft visited.
If you are interested and ready, then, please, grab your Passport to Nature! The trip is about to begin.[wc_divider style=”solid” line=”single” margin_top=”” margin_bottom=””]
Bill and Vicki Sherwood will be presenting for our Passport to Nature series on Astronomy Wednesday August 9th at 7pm. To register and find more details please visit our website events calendar here, or call the office at 705-326-1620.
Bill Sherwood is a volunteer and citizen scientist at The Couchiching Conservancy, a non-profit land trust dedicated to protect nature for future generations (including dragonflies).