When Temperatures Climb, Bodies Shrink

There's more and more talk (justly so, in my opinion) of global warming. This effect, though not new (NASA states that "just in the last 650,000 years there have been seven cycles of glacial advance and retreat, with the abrupt end of the last ice age about 7,000 years ago), still engenders dramatic (even catastrophic) changes. And the increase in temperatures we're seeing now, is the most rapid one the world has seen thus far (the increase in CO2 levels that caused the Great Dying, aka the greatest extinction event ever seen on Earth, was only 1/10th of the current increase rate we're seeing now).

One of these changes, as studied by Jennifer A. Sheridan and David Bickford, is the change in body size. Or, to be more precise, its shrinking. Which, as stressed out in their paper, "could negatively impact both crop plants and protein sources such as fish that are important for human nutrition." An ever more pressing issue as the global population keeps expanding, despite doing so at a slowing rate.

Here are some interesting details from their paper:

1. The increase in temperatures and the resulting change in rain patterns will affect every organism on the planet.
2. However, although each organism should see "shrinkage", this won't happen all at once nor equally across all species, which means that our whole ecosystem will be even more out of balance.
3. What will shrink? Everything, including:
1. Oysters, scallops, and corals (some of which may even disappear entirely since they wouldn't be able to form exoskeletons anymore).
2. Phytoplankton, which is the food base for most marine life, and, incidentally, is also the plant that absorbs most of the CO2 on Earth.
3. For every 1°C of temperature increase, the following drops in mass/size are expected (as examples):
1.  fruit: 3-17%
2. marine invertebrates: 0.5-4%
3. fish: 6-22%
4. beetles: 1-3%
5. salamanders: 14%
4. The downsizing trend has already started, by the way, and evidenced through studies of creatures in the wild as well as those subject to commercial harvesting. These organisms include polar bears, red deer, toads, squirrels, birds, plants, sheep. Scientists and farmers have also seen that cows follow the same trend in hotter temperatures, thereby also producing less milk.

   

   Source: Journal of Dairy Science

5. Evidence of such massive size reduction is also supported by fossils, which show, for example:
1. Bees, wasps, spiders, beetles, ants, and cicadas shrank by 50-75% in size almost 55 million years ago, when global temperatures suddenly jumped 3-7°C and rainfalls dropped by ~40%. 
2. Similar shrinking was observed on small mammals during other global warming periods:
1. An early horse got 14% smaller (granted, it wasn't a very big horse to begin with, going from the size of a dog to that of a cat)
2. Early primates got 4% smaller.
6. Other changes to expect from global warming:
1. Melting glaciers.
2. Rising sea levels (definitive flooding of land).
3. Acidification of all water sources--marine and fresh.
4. Increased ultraviolet-B radiation (risks to humans include: skin cancer, reduced immune response to Herpes, skin lesions, harm the spleen, eye problems; risks to plants include: impaired photosynthesis so less oxygen's produced, size reduction, drop in overall production, increased susceptibility to disease, changed flowering pattern).
5. Increased fire frequency.
6. Less rain/precipitation globally; and for those places with more rainfall, will see it happen all at once, with long stretches of water limitation.
7. Subtropics will get drier while much of the equatorial and high-latitude regions will get wetter (fewer habitable areas for humans)--linked to points 5 and 6.
8. Nutrient loss (either to excessive soil nitrogen loss through fires, or leaching due to too much rain at once).
9. Extermination of many species that can't adapt quickly enough.

I know. Lots of data to take in. And scary. A few percentage points might not seem like much, but they can mess up the balance of life on earth completely.

Already, as reported in The New Yorker in 2018, the number of chronically-malnourished people and the number of children forced into labor has started to grow again, "driven in part by an increase in conflicts and climate-induced disasters."  And that's "only" with a 1°C increase over pre-industrial temperatures. The article also mentions other effects from global warming that we're suffering from right now, such as: an increase in Lyme disease (Are there ticks on that beautiful green lawn? Should I still have my BBQ party?), proliferation of jellyfish (paddling among a cloud of medusas while out surfing doesn't sound so cool).

It's going to happen, it's happened before. The question is, by how much will temperatures rise, how quickly, and will we be ready to face the consequences (or have solutions to help protect our flora and fauna as much as possible) when the time comes?

N. America after sea levels rise due to ice melts

Europe after sea levels rise due to the melting of the ice caps

Sources:
NASA - Global Climate Change
World Population Clock
Shrinking body size as an ecological response to climate change, by Jennifer A. Sheridan and David Bickford
Global warming shrank animals in the past, article in USA Today, March 18, 2017
How Extreme Weather is Shrinking the Planet, by Mill McKibben for The New Yorker, November 26, 2018
What the world would look like if all the ice melted, National Geographic
Ultraviolet Radiation: How it Affects Life on Earth, NASA - Earth Observatory

Demon Duck Of Doom

No, this isn't the title to new B-rated horror movie (though it could be). It is instead the pet name given to the Bullockornis, a 2.5 m tall duck. Although I suppose he'd be considered to be more of a giant cousin of the dodo (also extinct) in that it was a flightless bird (getting 500 kg into the air is no small feat, after all). It lived about 15 millions years ago in (where else?) Australia!

I wonder if they could replace our modern-day horses (I know people have tried riding ostriches)--they could've been like chocobos!

It's all fun to imagine such a large bird waddling except for the tiny, very minor detail that it was quite possibly carnivorous and its beak sharp and strong enough to shred through flesh. So perhaps it's for the best that most animals have shrunk over the eras (reasons for this include a change in oxygen levels and the climate, for example) or have been locked up inside Jurassic World :)

Sources:
Prehistoric wildlife
Te Ara

Humanity's Tipping Point

I've just finished reading a(nother) fantasy book--Midnighters #3: Blue Noon--where one of the characters, Rex, considers the potential end of the world. For humans at least:

In the darkling part of his mind, Rex thought for a moment that perhaps this wasn't such a bad thing. Without predators to cull the herd, humanity had spread across the earth unchecked, crowding the planet beyond its resources, prideful and arrogant.
Maybe one night a year of being hunted would do them good.

Though one night a year may not seem like a lot, in this book it equates to thousands of deaths, if not millions. Granted, out of 7+ billion people, that's a pretty small number, but still.

Anyway, I know that end-of-world stories, or at least end-of-humanity stories have been quite popular lately (with zombies only being one aspect of them), and I think they do bring up an interesting point: considering we're at the top of the food chain (with nothing to cull our population growth), then how long can we continue on this path before we've outgrown our environment?

Population growth is currently at 1.14% per year. Granted, the rate has supposedly started to decline again (thanks to developed countries), but just over the 20th century the world population grew 264%, from 1.65 billion to 6 billion. Now that's not chump change.

So, since as Harvard University sociobiologist put it, "[t]he constraints of the biosphere are fixed," how many humans can our little Earth sustain? About 9 to 10 billion (according to some scientists). That's not much higher than our current level and, according to predictions, is a number that should be hit between 2040 and 2062. So in 25 to 47 years. Or relatively soon and, in most people's case, our lifetime.

Exciting news, isn't it?

So what are we to expect then? Short water supply (better start stocking up on those bottles!), short food supply (makes us feel bad about wasting 1.3 billion tonnes of food every year, doesn't it?), To make the picture a little bleaker, the 10 billion sustainability mark is assuming everyone becomes a grass-eater (vegans FTW!), so a more realistic picture would bring down that mark... Although, considering the current specie extinction rate is 1,000 to 10,000 times higher than the natural extinction rate (aka background extinction rate: rate of extinction without human involvement), that means between 200-2,000 (on the low end) or 10,000 to 100,000 (on the higher end) species are becoming extinct, I have a feeling this constrains our biosphere parameters even further. Robot bees just aren't going to be enough to make a difference...

So all you zombie/apocalypse fan boys and girls there might get to experience survival scenarios (who knows how people would react in such a world?). As for everyone else, well, let's hope we figure something out, and soon. (I'm totally for colonizing Mars, btw!)

In the meantime, I'm going to enjoy my time with my family and friends that much more and appreciate my Christmas dinner fully (with no wastage!).

UPDATE - 2015.01.22:
Just read this article about humanity tipping the earth's ecological and weather patterns into unsafe zones, with already two large "dead zones" reported, and more to come if we keep up with our current activities (especially the production of the chemicals phosphorus and nitrogen). The scientists in charge of the study stated that we've hit 4 out of the 9 "safe operating space" boundaries, getting closer and closer to the point of no return where life won't be as friendly as it has been up until now...

Sources:
Live Science - How Many People Can Earth Support?
World Population Clock (with amazing charts!)
UNEP - Food Waste Facts
WWF - How Many Species Are We Losing?
Center For Biological Diversity - The Extinction Crisis
Robobees

All Hail The Hero Pigeon

Carrier pigeon

As in any war, being able to transmit messages is crucial--how else is one to transmit orders and organize the troops so that they move according to plan? During World War I, these messages were transmitted in several ways, including via wire (telephone/telegraph lines). But putting up those lines was a very dangerous job, and sometimes impossible. So sometimes a field commander would carry carrier pigeons with him as well. The pigeon, carrying the message in a small capsule on one of its legs, would fly back to its home coop behind the lines. Upon arrival, the wires in the coop would sound a bell, signaling that a new message had arrived.

Pigeon being sent with a message.

Cher Ami was one such pigeon during WWI.

On October 3, 1918, Major Whittlesey and more than 500 men from the Liberty Division (since most men were from New York) were trapped on the side of a hill, surrounded by enemy soldiers. The next day, only 200 men were left alive. Major Whittlesey sent out several pigeons for aid. The next day, the American Artillery tried to save them by firing hundreds of big artillery rounds into the ravine where the Liberty Division was stuck...without knowing the American soldiers' exact location and thereby dropping big shells right on top of them.

So Major Whittlesey sent out his last remaining pigeon, Cher Ami, into the fray, with a single note:

We are along the road parallel to 276.4.

Our own artillery is dropping a barrage directly on us.

For heaven's sake, stop it.

Croix de guerre

The little bird flew through the shots (for the Germans saw it take flight and wanted to prevent it from reaching its destination) and made it home, some 25 miles away, in 25 minutes, to deliver his message. The soldier who went to fetch the message found Cher Ami had been shot through his breast leaving a hole the size of a quarter behind, blinded in one eye, and, attached to his almost entirely severed leg, was the message.

Thanks to Cher Ami, 194 men were saved that day. The medics were hard to put him back together, and the French honored him with the Croix de Guerre and, when he was better, he was brought back to the US.

Source:

Home of Heroes

The Genetic History Behind The Fastest Runner On Earth

Cheetahs, with their wiry bodies, mega-strong legs, small heads, and incidentally very rough fur that makes
them unlikely targets for poachers, can go from 0 to 70 miles/hour in the span of 4 brief seconds (though that only lasts for about 0.25 miles).  However, they also have a low fertility rate (low sperm count: about 10% of the norm for other cats), a high percentage of birth defects (about 70% of the sperm malformed), and weak immune systems :(

But blood tests brought about a really interesting discovery: this may all be caused by waaaaay too much interbreeding (and we know all how badly that's turned out for some "royal specimens"--see here, here and at the bottom of this post), to the point that it appeared every single cheetah on earth was merely a clone of itself.

It was found that some 12,000 years ago, the cheetah species went through some apocalyptic event (think Ice Age) that wiped out all but a few lucky survivors... the ancestors of our current cheetahs.

Cool fact: females are loners (except when taking care of their cubs) whereas males can travel in packs, and it's the females who pick their own partners!  (Also, if two or more females share the same space, they "may suppress each other's reproductive hormones.")

For you history buffs out there (not completely unrelated):

Class case of inbreeding: King Charles II of Spain who was physically and mentally disabled, and infertile.
Note that in Ancient Egypt, the Pharaohs had to marry their sisters to get a true heir.

And this one's kinda sad, actually, but another good example of the dangers of inbreeding:

Source:
Smithsonian Magazine