These findings are particularly fascinating because it has been a long-standing mystery as to whether rangeomorphs were closer to plants or animals. But according to a new study, their reproductive techniques were astonishingly complex – and familiar, too.
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Rangeomorphs are creatures from the enigmatic Ediacaran biota.
Scientists will focus on the identification of other particularities of the ancient species to better understand the evolution of the Fractofusus and hopefully, to determine whether they are plants or animals. “The capability of those organisms to modify between two distinct modes of copy exhibits simply how refined their underlying biology was, which is exceptional at a time limit when most different types of life have been extremely easy”.
Looking like trees or ferns, fossils reveal they did not appear to have mouths, organs, or means of moving, and probably absorbed nutrients from the water around them.
“Rangeomorphs don’t look like anything else in the fossil record, which is why they’re such a mystery”, lead study author Emily Mitchell, a postdoctoral researcher in Cambridge’s Department of Earth Sciences, said in a statement.
“But how rangeomorphs relate to animals and the origins of animals is incredibly hard to work out”. Like other rangeomorphs, Fractofusus was immobile, and so its fossils capture exactly where the creatures lived in relation to one another during the Ediacaran period.
With a high-res Global Positioning System device, Mitchell and her colleagues noticed evidence of two reproduction methods when examining the Fractofusus fossil. The second and third generations of the creature were connected by runners sent out by the older generation like strawberry plants. Plants were able eject little pieces of themselves out into the ocean, where these seed- spore-like propagules could be carried to new territory. The larger Fractofusus, or “grandparent” specimens, were randomly distributed around the environment, surrounded by distinctive populations of smaller “parent” and “children” Fractofusus, the researchers said.
The “generational” clustering suggests that Fractofusus reproduced asexually but it’s still unclear if the waterborne seeds or spores were sexual or asexual in nature.
Essentially, the rangeomorphs sent out an “advance party” to settle in a new area, then rapidly colonized the area.
This illustration shows a Fractofusus reproduction pattern.
“The complexity of Fractofusus’ reproductive mode is intriguing, in part, because it would be surprising if large complex organisms hadn’t existed prior to this development”.
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This is not the first time a clustering reproduction was reported in pre-Cambrian. To that end, they may have made some progress: about 565 million years ago, there was a creature in Earth’s oceans that scientists now considered to be the oldest example of complex organisms procreating.
