Friday, June 22, 2018

Bye Bye Baobabs

Ancient life: Elephants in Tanzania rub against an old baobab, a type of tree that a recent report notes has suffered a huge decline in population in the past 50 years. | GETTY IMAGES

Baobabs a wake-up call for action on climate change

The Japan Times  by Rowan Hooper  Special To The Japan Times
I’ve been writing about science and nature for many years now, and I still think it’s one of the best ways to feed and nurture a sense of curiosity. But constant exposure to scientific publications can sometimes blunt their impact.

I might take an amazing discovery for granted, or feel only numbness at the latest study on the potential impacts of climate change, for example.

But every now and then a study comes along that cuts through the haze. That happened earlier this month when scientists from Babes-Bolyai University in Romania published a report on baobab trees in Africa.

Trees come in two basic types — coniferous and flowering trees — and baobabs are the largest and longest-lived of the flowering type. 

They live for thousands of years. Some of them alive now were growing when the Roman Empire was ruling Europe, and during the Yayoi Period (200 B.C.-A.D. 250) of ancient Japan, when the native people of the islands started to be displaced and absorbed by new immigrants from the Asian mainland.

Their extraordinary longevity alone makes baobab trees things of wonder. But they are also hugely important parts of the ecosystem, and vital to people who live near them. So the report of the deaths of many of these ancient organisms is shocking and tragic.

Adrian Patrut’s team was studying some of the oldest baobabs in Africa when they realized that some were dying. Over the past 12 years, nine of the oldest trees have died. Patrut estimates that half of all baobabs have died in the past 50 years: a short period in the life of such long-lived trees. Many younger trees have also died, and Patrut blames climate change. His work is published in the journal Nature Plants.

We used to refer to climate change as “global warming,” but that misses sight of the fact that the planet isn’t just warming up. 

Patterns of rainfall are changing, so there may be longer periods of intense drought, and episodes of disastrous flooding. Summers might be wetter as well as warmer, and winters colder. Many things in the complex climate and weather system of the planet are altering, and many organisms can’t adapt in time to survive.

Add to that the downturn in the growth of new trees, and the baobab might be in trouble. Elephants eat the baobab fruit and spread the seeds in their dung, but elephants themselves are being poached and killed and do not travel as freely as they once did.

It sometimes takes a threat to an iconic species to make people sit up and take notice. It happened in the 1970s and ’80s when many species of whales were hunted to near extinction. Polar bears, chimpanzees and pandas are the charismatic and endangered species we hear a lot about today. Add to that the magnificent baobab.

Of course, many less charismatic organisms are in deep trouble. In Japan alone thousands of endemic species are classified as endangered, including dozens of species of birds and mammals, a third of all reptiles, and hundreds of insects and plants.

Let’s put it another way. Instead of looking at iconic species, look at iconic masses of land. The future of Antarctica, currently the most unspoiled of all continents on the planet, is in the balance. The decisions we make now will determine whether huge parts of Antarctica disappear.

A recently published study models what will happen if we don’t make cuts in emissions of carbon dioxide produced by our rampant consumption of fossil fuels. If we continue as we are, then in just 50 years the warming of the planet’s atmosphere and ocean will have caused extensive melting of the Antarctic ice shelves. This in turn will cause a large rise in sea levels around the world, and the flooding of coastal cities. We need to preserve the rules that currently forbid the mining and exploitation of the continent.

Martin Siegert, of the Grantham Institute of Climate Change at Imperial College London, warns that we are at a critical point.

“If the political landscape of a future Antarctica is more concerned with rivalry, and how each country can get the most out of the continent and its oceans, then all protections could be overturned,” he said
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“However, if we recognize the importance of Antarctica in the global environment, then there is the potential for international cooperation that uses evidence to enact changes that avoid ‘tipping points’ — boundaries that once crossed, would cause runaway change.”

Siegert’s words apply more broadly than to the southern continent. The baobab news is the latest in a series of wake-up calls. We can’t delay meaningful action on climate change any longer.

Rowan Hooper is the managing editor of New Scientist magazine. His new book, “Superhuman: Life at the Extremes of Mental and Physical Ability,” is out now. Follow him on Twitter @rowhoop.

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