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Fabian Weston makes videos of tiny organisms filmed under a microscope.
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One of his videos provided the missing piece to connect 400-year-old fossils with living euglenoids.
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Euglenoids may be some of the earliest eukaryotes, the domain that includes plants and animals.
Sometimes, it really helps to Google it. Especially when you are a stump scientist who is all exhausted.
That’s what one research team did after all else failed. And it helped them solve a scientific mystery that has puzzled biologists for decades.
400-million-year-old microscopic fossils
There have been five mass destructions on Earth. Some events killed off 95% of living species. Euglenoids survived them all.
“Euglenoids are microscopic life forms that combine the characteristics of both animals and plants,” Bas van de Schootbrugge, professor of geosciences at Utrecht University, told Business Insider via email. They eat like animals and photosynthesize like plants.
You can find the organisms in freshwater ponds around the globe, said van de Schootbrugge. But they are rarely found in the fossil record, even though they have been around for some time.
To find evidence of ancient euglenoids, van de Schootbrugge and his colleagues looked at microfossils – teenage fossils that are only a few millimeters in size.
“We worked on the assumption that these microfossils could be euglenoid cysts, but no one had seen an euglenoid forming a cyst in nature or in the laboratory,” said van de Schootbrugge.
Going back 400 million years, some euglenoids made cysts that protected the organism during unfavorable conditions. But it was not clear what these funds looked like.
A chance to look at a YouTube video helped van de Schootbrugge and his colleagues connect the fossils with the living euglanoids.
The finding could help establish euglanoids as some of the earliest ancestors of all living plants and animals.
The proof was in a pond (and on YouTube)
There were two main problems with cystic microfossils: their name and their appearance.
“People working in different time slices essentially gave different names to the same type of microfossil, which obscured its long evolutionary history,” said van de Schootbrugge.
They were the Paleozoic Comotriletes, Mesozoic Pseudoschizaea, and Cenozoic Concentricystes. The researchers went through 500 papers to find references to all the different names.
Other scientists have noted the similarities between all these microtraumas, but “the cysts have a structure that is unlike anything seen before,” said van de Schootbrugge. Since no one had documented an euglenoid that made a cyst, there was nothing from today to compare the ancient examples to.
And then one of van de Schootbrugge’s co-authors, Paul Strother, came up with “Cysts Eugene” and a result on YouTube came up.
In the video, Fabian Weston was showing a pond water sample under a microscope. The New South Wales resident has a YouTube channel dedicated to filming all kinds of microscopic organisms.
In the video below, you can see Euglena form into a thick-walled, ribbed ball. “The cysts look layered, and this may be taken from the mucus that is usually on the outside of certain euglenoids,” said van de Schootbrugge.
“After watching it, we were convinced that what was seen in the video was Euglena making the kind of structures that we see as microfossils,” said van de Schootbrugge.
It was the missing piece.
“What we did, in fact, was connect the most recent living forms, which connected the taxonomic names to the living microorganisms,” Strother told Business Insider via email.
They recently published their paper in the peer-reviewed journal Review of Palaeobotany and Palynology..
Van de Schootbrugge noted that they have not yet seen Weston’s own cysts and hope to look in the pond sediment for Comotrilete microfossils.
The evolutionary tree of life
Strother believes this study is a piece of the eukaryotic Tree of Life (eTOL) puzzle. Eukaryotes are the organic domain to which all animals and plants belong. Unlike bacteria, their cells have a nucleus.
In other words, they are some of our earliest eukaryotic ancestors.
Scientists think that euglenoids may have evolved more than a billion years ago, according to a press release about the study. Knowing which eukaryotes evolved first is a big step in understanding how they lived so long.
Extending the fossil record of euglenoids as far back as geological history suggests they are among the oldest eukaryotes, Strother said, adding that the question this work addresses – but not need to ‘answer’ – not, ‘Which species is the root of the eTOL?'”
Read the original article on Business Insider
