(ORDO NEWS) — Sponges are very primitive and ancient creatures that are among the main components of reef ecosystems.
They have long lived in close symbiosis with microorganisms, and now scientists have reconstructed the evolution of sponges using a “genomic time machine”.
Outwardly, sponges are something shapeless and motionless, but from the point of view of biology and biochemistry, they are very peculiar.
In addition, sponges played a huge role in the past of the biosphere and participated in the formation of the first marine ecosystems, and now they remain an important component of coral reefs, along with intestinal polyps.
Sponges live at the bottom of water bodies (mainly seas) as part of the so-called benthos or attached to submerged objects – in this case they are referred to as foulers (periphyton).
They have no mouth, no intestines, no sense organs, let alone any behavior – but they tirelessly pump water through themselves and extract an organic suspension from it.
This is the food of sponges. In addition, they are highly dependent on microscopic symbionts (including bacteria and other single-celled lifeforms) that inhabit their bodies.
“This study made it possible to understand how one of the groups of organisms acquired their microbiomes more than 700 million years ago,” says Sabrina Pankey from the University of New Hampshire (USA).
She highlights the increasing proportion of sponges in coral reef ecosystems against the backdrop of climate change, as well as their role in water purification and nutrient uptake.
Nearly 100 species of sponges living in the Caribbean have become the object of a new study. The scientists created a model of each of the unique microbiomes that inhabit individual sponges. It turns out that they should be divided into two clearly distinct groups.
Microbes from the first are mainly involved in the nutrition of the sponge. At the same time, microbiomes of the second group are needed to protect the sponge (and hence its symbionts) from being eaten by animals.
As the authors note, these communities are very complex and suggest that sponge microbiomes developed independently and reappeared several times.
The value of the new publication is not limited to such unusual creatures as sponges. It proposes a new approach based on genome sequencing, DNA barcoding and special machine learning algorithms.
Since the new methodological approach makes it possible to reconstruct the evolutionary past of genomes, the researchers called it the “genomic time machine”.
“If we can recreate the evolutionary history of such complex microbial communities, at the same time we will learn a lot about the history of the Earth,” says one of the co-authors, David Plachetzki (David Plachetzki).
“Scientific studies like ours are helping to better understand what the chemistry of the oceans on Earth was like long before the advent of coral reefs.” Plachecki and his colleagues managed to find out that the appearance of oceanic reefs coincided in time with sharp changes in the biogeochemical conditions on Earth.
Professor Plachecki also suggests that their technique will be useful in finding out the causes of the greatest extinction in the history of the Earth, which occurred at the end of the Permian period and killed 95% of the inhabitants of the seas.
—
Online:
Contact us: [email protected]
Our Standards, Terms of Use: Standard Terms And Conditions.