Snake Compass

Python skeleton Source: Worrapol Koranuntachai /123rf

Python skeleton
Source: Worrapol Koranuntachai /123rf

Burmese pythons (Python bivittatus) are a successful invasive species in Florida that have been profiting from local wildlife and few natural predators. Native to Southeast Asia and listed by the IUCN as vulnerable or endangered in their original habitats, abandoned or escaped pythons have been thriving in the Florida Everglades, to the dismay of conservationists trying to protect indigenous species there. Not much is known about how the snakes move or take up a new residence.

As it turns out, pythons have a distinct sense of  direction and territory when it comes to their habitat. A recent study published by the Royal Society journal Biology Letters suggests that pythons use a homing instinct to venture out from their usual territory and then find their way back.

A research team tracked several pythons – some of them trapped and removed miles away from their territories, some left in their adopted areas – to see whether the snakes that had been removed would be able to find their way home.

Source: Deimos in Flames / Deviantart

Source: Deimos in Flames / Deviantart

And indeed, all the relocated snakes demonstrated great determination to return to where they’d been captured in the first place. Most of them succeeded in finding their way back. The snakes which had been tagged and released without relocation moved around within a much more limited area, usually returning to their own territory.

The snakes clearly have both a ‘map sense’, which tells them where they are in relation to ‘home’, and a ‘compass sense’, which tells them in which direction to guide their movement. And it’s likely that this ability isn’t limited to the Burmese python – snake navigational abilities just haven’t yet been widely studied across many species.

According to this article, researchers say the internal python map “could be magnetic, like sea turtles, while the compass could be guided by the stars, olfactory (smell) cues, or by polarised sunlight – all of which have been shown to be used by reptiles.” Gaining knowledge of how snakes travel and navigate should prove useful in controlling their spread.

What I find interesting is how well the Burmese python has adjusted its internal compass to an entirely new corner of the planet from where it evolved. Having said that, another study published late last year suggests that Burmese pythons are among the most rapidly evolving vertebrates in the world.

How did the Burmese python learn to redefine home so quickly?

Source: gortan123/123rf

Source: gortan123/123rf

Reaching New Shores

Circular plot of migration flows of at least 170,000 people between and within world regions during 2005 to 2010. Tick marks show the number of migrants (inflows and outflows) in millions.  Click to enlarge.  Image courtesy of Abel et al., Science/AAAS via Co.Exist

Circular plot of migration flows of at least 170,000 people between and within world regions during 2005 to 2010. Tick marks show the number of migrants (inflows and outflows) in millions.
Image: Abel et al., Science/AAAS via Co.Exist

The Intergovernmental Panel on Climate Change (IPCC) recently released a report on the development of climate change and its effects on humans.

The 2600-page report is the result of three years work and the collaboration of 300 scientists.

It makes for mostly grim reading, with an emphasis on climate impact on food security (not positive), on extreme weather events (increasing), and on poverty (again, not positive).

The global migration patterns in the interactive graphic above illustrate twenty years of migration statistics from 196 countries. Created by the Wittgenstein Centre for Demography and Human Capital in Vienna, the graphic uses software lifted from the field of genetic research.

It’s interesting to note that the number of people who actually leave their country of birth for good has remained at more or less the same level across decades – a mere 0.6% of the population. As a long-term expat among many long-term expats, it often seems like the number must be much higher, but such is the power of subjective perception. What we think we see up close isn’t always what’s happening if seen at a distance.

Quoted in Co.Exist, the authors say, “These long-distance flows are effective at redistributing population to countries with higher income levels, whereas return flows are negligible.” So, migration has been for mainly economic reasons, or for reasons of security offered in higher-income countries.

Given the IPCC report and its sobering conclusions regarding food security and extreme weather events, I wonder how these migration patterns and numbers will develop over the next few decades – which areas will see more migration inflow. The higher ground countries as well as those with higher-income?

Will we as humans follow many animals, flee an ever-warmer planetary midsection, and migrate north?

And what about that migration number of people who permanently leave their home country, 0.6%, that’s been steady for so long? Should climate change redraw the coastlines of continents and the boundaries of nations, what will count as ‘migration’ and what will count as keeping one’s head above water?

The World - Rising Sea Level, first map of its kind on such a scale and level of complexity, depicts our planet as it would look without its polar ice caps, with sea levels 260 ft higher as they are today. Click map for a larger version. Artist: Jay Simons

The World – Rising Sea Level, first map of its kind on such a scale and level of complexity, depicts our planet as it would look without its polar ice caps, with sea levels 260 ft higher as they are today. This detailed map can be viewed in all its glorious cartographic futurism by clicking on the map or following the link of the artist, Jay Simons.
Click map for a larger version.
Artist: Jay Simons




Staking Territory 1

Image: 123rf

I’m always interested in the way creatures find to mark their territory, the variations in what can be considered grounds for competition. Physically marking territory for hunting by using scents; territory for mating by using struts, plumage or howls; fencing and barbed wire for farming. Staking territory to gain an advantage is probably almost as old as life.

When it comes to humans, we have invented systems for staking out the territory not just of where we are, but what we think. We call our thoughts intellectual property and we claim that property using patent and copyright law.

There’s a discussion over territory that’s both physical and intellectual that’s going on right now in the U.S. Supreme Court. On one side is a 75-year-old Indiana farmer, Vernon Hugh Bowman, who planted soybeans he purchased from the Monsanto company. They were Roundup Ready soybeans, which are engineered to be resistant to weedkiller. In the 15 years since its introduction, the Roundup system has grown to comprise 90% of all soy grown on U.S. soil.

When farmers buy Roundup Ready seeds, they sign agreements that they will not plant the seeds from the original plant for a new crop. The 2nd generation seeds contain the same engineering as the parent seeds, and each plant provides up to 80 new seeds. Most farmers comply. Mr. Bowman did not. He planted the 2nd generation seeds, and when Monsanto sued him for breach of contract, he went to court. And lost. He appealed, and lost again. Now the case is in front of the Supreme Court, and Mr. Bowman is appealing with the assistance of a large lawyerly contingent.

Their argument is that the Monsanto patent only extends as far as the seed generation that was sold and planted. Farmers have been saving seeds from one year to replant the next for millennia – it’s called agriculture. To limit the right to do so is to limit human culture by limiting choices to those products made available by a very few companies.

Monsanto doesn’t agree. The company spends vast amounts of money on research and development. If it can’t recoup that investment by selling its products, there is little incentive to develop new and useful technologies. Many business leaders and economists agree. “Our case is the template for a broader discussion,” said David Snively, Monsanto’s general counsel. “This is just really about how patent law concepts apply to tomorrow’s technologies.”

The United States has only allowed the patenting of living organisms since 1980 (Diamond v. Chakrabarty). As one article sums it up:

The difference here, some attorneys say, is that the patented item is a product of nature that regenerates on its own.

“Are they going to take nature into account? Are they going to take into account that this is what beans do?” asked Yvette Liebesman, a law professor at St. Louis University. “You can patent anything under the sun created by a human. If a plant is doing what plants do, is that something that humans have done?”Locked-garden-gate-web

Monsanto has an answer for that.

“This is not just a seed,” Snively said, “and to suggest that plants just grow themselves is preposterous.”

There have been calls recently to overhaul patent law, claims that it stifles real innovation and productivity. This is a topic I’ll explore later with regard to green issues.

For now, I will be watching Mr. Bowman and Monsanto use whatever means at their disposal to stake out their respective territories. It’s what we do.