JoNova

A science presenter, writer, speaker & former TV host; author of The Skeptic's Handbook (over 200,000 copies distributed & available in 15 languages).



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Salmon quite happy to adapt to warmer world

You will never guess, but salmon that survived the hot Holocene period, and the even hotter Eemian, will probably be OK in a slightly warmer world. Expert researchers found this surprising.

Given the broad spread of Salmon in the Northern Hemisphere, and their past survival through every single interglacial warm period of the Pleistocene, I would have thought that they could cope with quite a bit of  climate change. As it turns out, they cope so well, that even salmon eggs that come from a 12C environment can be raised in an environment a whopping 8C warmer, and they were not noticeably any worse off.

Part of the concern with salmon was the spawning and eggs, and the problem with getting the salmon to shift their maternity wards and childcare arrangements (which they seem very attached too). But presumably those breeding grounds have varied before in temperature, and salmon didn’t die out, so — at least with this problem — nature has it figured out.

Map: Salmon and Climate Change, Fish in hot water, Red List.

Atlantic salmon also show capacity to adapt to warmer waters

Populations of Atlantic salmon have a surprisingly good capacity to adjust [...]

Whales dive to nearly two miles depth, hold breath for two hours

Friday curiosity: Duck-diving Cuvier’s beaked whales can hold their breath for over two hours, and reach a depth of 2 miles (3.2 km) underwater. What’s more, when they come up, they recover in an unbelievable two minutes. (Actually, I really do find this hard to believe. Two minutes? Seriously? )

Cuvier Beaked Whale | Oceanus Magazine Woods Hole Oceanographic Institution

These whales can go four times deeper than modern nuclear submarines which are estimated to have a hull crush depth of around 730m. Presumably the Department of Defence will be looking into blubber power or nuclear whales.

But seriously, whales and seals can hold their breath for a ridiculously long time because they pack a lot of oxygen away in their muscles — it’s attached to myoglobin which they have in abundance. Myoglobin‘s quite a lot like the haemoglobin molecule found in blood, it uses iron to bind the oxygen.

For a completely useless culinary tip, whale meat is thus the absolute reddest-of-red-meats and very iron rich –  “perfect” then,  for anemic vegetarians.

Scientists monitored Cuvier’s beaked whales’ record-breaking dives to depths of nearly two miles below the ocean surface and some dives lasted for over [...]

Zebra Fish like it warm – they swim faster and adapt even better to climate change

Experiments with Zebra Fish show that if their embryo’s develop in warmer water, they not only are able to swim faster but they cope better in both warmer and colder water. (How catastrophic can that be, I ask you?)

ScienceDaily (Aug. 14, 2012) — New research by McMaster University biologist Graham Scott suggests that growing up at warmer temperatures helps some aquatic animals cope with climate change, raising questions about the limits of adaptation.

Scott and Johnston found that when embryos raised in warm water experienced temperature variation as adults, they could swim faster, their muscle was better suited for aerobic exercise, and they expressed at higher levels many of the genes that contribute to exercise performance.

The improvements were true for the adult fish in warmer and colder water alike — a finding that surprised the researchers.

“We thought that they might do better under warmer conditions because they grew up in warmer conditions. We didn’t think they’d also do better under colder conditions, but they did.

Their research shows the fish are hardier after being raised in a warm-water nursery, and raises the question of how far the temperature [...]