Deadly lake turns animals into statues

Calcified bird

(Images: Nick Brandt)

According to Dante, the Styx is not just a river but a vast, deathly swamp filling the entire fifth circle of hell. Perhaps the staff of New Scientist will see it when our time comes but, until then, Lake Natron in northern Tanzania does a pretty good job of illustrating Dante’s vision.

Unless you are an alkaline tilapia (Alcolapia alcalica) – an extremophile fish adapted to the harsh conditions – it is not the best place to live. Temperatures in the lake can reach 60 °C, and its alkalinity is between pH 9 and pH 10.5.

The lake takes its name from natron, a naturally occurring compound made mainly of sodium carbonate, with a bit of baking soda (sodium bicarbonate) thrown in. Here, this has come from volcanic ash, accumulated from the Great Rift valley. Animals that become immersed in the water die and are calcified.

Photographer Nick Brandt, who has a long association with east Africa – he directed the video for Michael Jackson’s Earth Song there in 1995 – took a detour from his usual work when he discovered perfectly preserved birds and bats on the shoreline. “I could not help but photograph them,” he says. “No one knows for certain exactly how they die, but it appears that the extreme reflective nature of the lake’s surface confuses them, and like birds crashing into plate glass windows, they crash into the lake.”

When salt islands form in the lake, lesser flamingos take the opportunity to nest – but it is a risky business, as this calcified bird (top) illustrates. The animals are all arranged in poses by the photographer. Above, on the right we have a sea eagle and on the left a dove, in what is surely the most horrific depiction of the “bird of peace” since Picasso’s Guernica.

Brandt’s new collection of photos featuring animals in east Africa, Across the Ravaged Land, is published by Abrams Books.

X-Ray Reveals How Bats Take Flight

Fluoromicrometry of bat in flight

By Megan Garber from Mashable.com:
Bats-flying
If you have seen a bat in nature — which is to say, if you have seen a bat that will go on to haunt your nightmares, mercilessly — you have probably seen the creature in one of two situations: in mid-flight, or hanging upside-down, sleeping.

It’s unlikely, though, that if you’ve seen a bat, you spotted it in the act of takeoff. Which means that you probably haven’t seen a bat in the middle of an activity that has long perplexed biologists. Bats may be the only mammals capable of true, sustained flight, but how, exactly, do they get to flying in the first place?

A group of scientists at Brown University investigated the matter, using XROMM (X-ray Reconstruction of Moving Morphology) technology that integrates three-dimensional renderings of animals’ bone structures into X-ray video. (XROMM data allow researchers to conduct detailed analyses of animals’ muscle mechanics and anatomy as the creatures moves.)

Video (scroll down).

The team looked in particular at Seba’s short-tailed bats — fruit bats — X-raying the creatures as they lifted themselves off the ground. Analyzing the videos that resulted, the researchers made a discovery: Bats seem to take off into the air by stretching out the tendons that anchor their bicep and tricep muscles to their bones. They then compress the tendons to release energy and power their flight upward.

It seems, in other words, that bats’ stretchy bicep and tricep tendons are crucial for storing and releasing the energy the creatures require for takeoff. As research lead Nicolai Konow explained it:

By combining information about skeletal movement with information about muscle mechanics, we found that the biceps and triceps tendons of small fruitbats are stretched and store energy as the bat launches from the ground and flies vertically.

The bats’ stretchy muscle analysis seemed to be confirmed by the team’s use of another technology: fluoromicrometry, in which small, chemically labeled markers are implanted directly into muscle — which in turn allows researchers to measure changes in muscle length during contractions with high precision.

And that’s a big finding. Most scientists had previously believed, Smithsonian Magazine points out, that small mammals’ tendons are too stiff, and too thick, to be stretched at all. The X-rays revealed otherwise, however, and the Brown team presented their findings last week at a meeting of the Society for Experimental Biology. And they’ve presented their videos to the rest of us, so that we may be appropriately astounded and creeped out by the unique biology of bats.

Image courtesy of Flickr, KajiFox

[Full article]

This article was originally published at The Atlantic here.