Natures wonders: early antifreeze development: (Introduction)

by David Turell , Monday, September 11, 2023, 19:20 (437 days ago) @ David Turell

In an arctic insect:

https://phys.org/news/2023-09-super-antifreeze-cells-ability-survive.html

"That was what the Earth looked like about 450 million years ago at the end of the Ordovicium period.

"The warm water created the perfect living conditions for wildlife. But this would soon change. Shortly after, the land masses would began to freeze and an ice cap start to spread.

"The water, which had previously been warm and accommodating to wildlife, became cold and inhospitable. One species after another succumbed. In a short period of time, half of all life had been wiped as part of the second-worst mass extinction in the history of the planet.

"One of the animals that survived, however, was the springtail. A small, insect-like animal that had developed a special strategy to combat the cold. The animal's cells had begun to produce proteins that could protect the cell from freezing.

"The springtail might have been the first animal to ever develop antifreeze proteins. Scientists had previously believed that animals didn't begin to do this until much later. This is shown by research from Aarhus University and Queen's University in Canada.

"'We knew that antifreeze proteins had developed independently of each other several times during evolutionary history. Fish have them. Insects have them. Some spiders have them. But until we saw these results, we didn't know that they'd developed so early in the animal world," says Martin Holmstrup.

***

"The springtail is a small animal, and the largest species of springtail are only six millimeters long. It has six legs and two antennae in front. It looks like an insect at first glance, but it's not. In fact, it has its very own branch on the evolutionary tree.

"So far, researchers have found more than 9,000 different species of springtail, and they can be found almost everywhere—including in your garden. Springtails typically live in the upper layers of soil or in fallen foliage, where they feed on microscopic fungi, bacteria and other microorganisms.

"The animal takes its name from its forked tail that it holds under its body like the bar of a catapult. The tail is also known as a furcula and the animal can release it quickly and leap up to 10 centimeters into the air if attacked by an enemy e.g. a spider.

"Springtails are good for the health of soil because they help recirculate nutrients to plants.

***

"Because the researchers know the DNA sequence that enables cells to build the antifreeze protein, they can search for the same sequence across species, families and ranks. They can also calculate when the mutation that led to the genesis of the gene occurred: the Ordovician period.

"'The calculations show that springtails developed the antifreeze protein long before other animals. It didn't happen for fish and insects until a million years later. Although plants and microorganisms, such as bacteria and single-celled algae, might have developed a similar mechanism even earlier," he says.

***

"Because the researchers know the DNA sequence that enables cells to build the antifreeze protein, they can search for the same sequence across species, families and ranks. They can also calculate when the mutation that led to the genesis of the gene occurred: the Ordovician period.
'The calculations show that springtails developed the antifreeze protein long before other animals. It didn't happen for fish and insects until a million years later. Although plants and microorganisms, such as bacteria and single-celled algae, might have developed a similar mechanism even earlier," he says."

Comment: Finding an exactly needed protein by chance is not a probable event. Convergent development of the same chemicals strongly suggests design.