Stepping outside the door of the place I’m staying in Madeira I’m met by a marvel. It’s 300 million years since insects like dragonflies evolved.
That’s nearly 300 million years before modern humans evolved.
They deserve some respect, don’t you think? They’ve continued to evolve and succeed in their ecological niches so there are 5,000 living species.
They can hover. They can fly vertically upwards and downwards. Their eyes take up most of their head. What’s not to like?
In the fossil record we find enormous dragonfly ancestors. Their size was enabled by the high oxygen levels in the atmosphere back in the Palaeozoic. Having 31% of oxygen rather than 21% of oxygen in the atmosphere meant they could grow to have 75cm wingspans and 46cm bodies. I breath deeply and imagine. That’s something insects can’t do. Insects have no lungs and have to ‘breath’ by exchanging gases through holes in their hard, crunchy exoskeleton. If they’re too big, then they can’t get enough oxygen to their vital organs or muscles and can’t get rid of the carbon dioxide fast enough.
They can’t imagine, either.
All those wondrous giants died off in the Permian mass extinction. Something happened 251.9 million years ago which killed off more than 96 in 100 of all marine species and 70 in 100 of all species on land. It’s likely that volcanoes released sulphur dioxide and carbon dioxide into the atmosphere, heating the Earth and acidifying the oceans.
It’s not hard to see the parallels with today’s sixth mass extinction.
This dragonfly is the Island Darter, Sympetrum nigrifemur. It’s only found in the islands of Madeira, Gran Canaria and Tenerife. It’s tiny, only four or five centimetres long, and it’s living on an extinct volcano.
It’s a small victory and a beautiful irony, of which it is unaware.