The current loop of our living ark is fairly circular. You may think that Earth's orbit is stable.
Our planet stretches out and becomes 5 percent elliptical every 405,000 years.
We have known for a long time that this cycle drives changes in the global climate, but we don't know how this affects life on Earth.
New evidence suggests that Earth's fluctuations could affect biological evolution.
A team of scientists led by Luc Beaufort, from the French National Centre for Scientific Research, have found clues that the photosynthesizing variety is driving evolutionary bursts of new species.
Plates of limestone are created around the soft, single-cellular bodies of caccialithophores. The coccoliths were first seen around 215 million years ago during the Upper Triassic.
Did you ever wonder how the White Cliffs were formed?
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They're made of microfossils. The coccolithophores produce calcium carbonate that fossilize and form chalk.
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Alison R. Taylor gave us this clip of coccolith formation.
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The project is called The FOSSIL Project.
The presence of these drifters can have a huge impact on our planet's systems because they are so abundant.
The 9 million coccoliths measured by the team were from the Indian and Pacific oceans. They were able to get a detailed resolution of around 2,000 years using well-dated ocean samples.
The researchers were able to estimate the number of species using the size ranges of the coccoliths, as previous genetic studies have shown that different species can be found in the Noelaerhabdaceae family of coccolithophores.
They found that the average length of a coccolith followed a regular cycle. After the highest eccentricity, the average coccolith size appeared to lag. If Earth was experiencing an interglacial state, this was not relevant.
The tropical band has the highest diversity of plankton in the modern ocean because of high temperatures and stable conditions, while the seasonal species turnover is highest at mid-latitudes.
They looked at the large time scales and found the same pattern. The seasons around the equator become more pronounced as the Earth's orbit becomes more elliptical. Coccolithophores were spurred to change into more species by the more varied conditions.
A higher diversity of ecological niches leads to a larger number of species because Noelaerhabdaceae adaptation is characterized by the adjustment of coccolith size and degree of calcification to thrive in the new environments.
There are different sizes of coccoliths across different time periods. Weimin Si.
The team detected a radiation event around 550,000 years ago which led to the emergence of the Gephyrocapsa species. The interpretation was confirmed using genetic data.
They were able to distinguish between local and global events by using data from both oceans.
The researchers were able to untangle the potential impact of different species on Earth's carbon cycle by calculating mass accumulation rates in the samples.
The team wrote that the lighter species contribute the most to coccolith carbonate export.
According to the findings and other supporting research, the lag seen between orbital eccentricity and changes in climate could hint at the fact that coccolithophores may drive rather than just respond to carbon cycle changes.
These tiny organisms, along with other phytoplankton, may help change Earth's climate in response to these events. There is more work that needs to be done to confirm this.
The research was published in a journal.
