Romancing the Stars

[Odysseus] never closed his eyes, but kept them fixed on the Pleiades, on late-setting Bootes, and on the Bear – which men also call the Wain, and which turns round and round where it is, facing Orion, and alone never dipping into the stream of Oceanus – for Calypso had told him to keep this to his left.

The Odyssey (Book 5) Homer

Celestial navigation is as old as the stars (I apologise, I couldn’t resist the pun!). The night sky was used as a navigation tool long before compasses were invented, and it helped most of the ancient explorers gad about the globe without maps. Even today, anyone who doesn’t trust Apple Maps knows how to orient themselves using Polaris in the northern hemisphere and the Southern Cross in the south.

But, like a lot of things we think we’re pretty good at, animals figured it out long before we did. Quite a few interesting experiments have shown that birds or animals can navigate using the stars and now, the dung beetle has become the first insect proven to navigate by the stars (although, maybe the ancient Egyptians already knew this when they elevated the dung-rolling scarab to sacred status?).

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Engineering Nature

Humans are the greatest ecosystem engineers.  We’ve already altered most of the world’s land surface through mining, agriculture and urban development; we’ve modified marine ecosystems through introduced species, commercial fishing and shipping infrastructure; chemical pollutants from our greywater entering waterways are creating inter-sex fish; and light pollution from our cities, and even from ski-runs, is altering behaviour, reproduction and circadian rhythms of resident wildlife.

Now even the mere sound of our existence is reworking Nature.  Noise pollution from development, airports, mining, and road traffic has always been an issue, not just as an annoyance to our own communities, but as a threat to nearby wildlife.  Animals and birds can abandon their habitats through fright, or be driven out because the human-made noise makes it too difficult for them to find food or mates.  Many birds and even whales have been forced to change the volume, sound frequency or timing of their calls to ensure they are heard above the din of human existence. Continue reading