Vampires are real. Apart from the well-known bats and truly horrifying aquatic lampreys, various other creatures are known to engage in a bit of blood-based theft, including a plethora of parasites and even one of Darwin’s Galapagos finches. However, as a new research paper highlights, there are far more violent vampires out there, and most of them are ancient.
Around 1.8 billion years ago, the eukaryotic domain evolved, which includes all organisms whose cells contain, among other things, a nucleus enclosed by a membrane. Susannah Porter, an associate professor in paleobiology at the University of California, Santa Barbara, was looking through a selection of 750-million-year-old microscopic eukaryotic fossils from the Chuar Group geological formation in the Grand Canyon when she realized that many of them had multiple puncture marks.
As she concludes in her study in the journal Proceedings of the Royal Society B, it’s highly likely that these holes were created by vampire-like amoebae that preyed on eukaryotes. If they caught their prey, they stabbed them repeatedly with a syringe-like appendage, used it to suck out their entire, nutritious insides, and effectively killed them from the inside-out.
The Chuar Group in the Grand Canyon used to be an ancient seabed. Carol Dehler
“We have a great record of predation on animals going back 550 million years, starting with the very first mineralized shells, which show evidence of drillholes,” Porter said in a statement. These aerated ancient seabed fossils, however, date back to between 742 and 782 million years ago. “To my knowledge these holes are the earliest direct evidence of predation on eukaryotes.”
The fact that so many of the holes were the same shape and size indicates that something deliberately and repeatedly caused them, and a microscopic predator is the only sensible explanation. The fossil of the ancient miniature predator, or predators, have yet to be found, so for now this evidence isn’t conclusive, but circumstantial – albeit very strong circumstantial evidence.
The circular holes, 10 times smaller than a typical grain of pollen, appear in up to seven eukaryotic species, all of which are likely to be photosynthesizing plankton. These ancient wounds were almost certainly “the work of tiny vampires,” as the author writes in her study.
They all resemble punctures made by several predatory protists – a group of eukaryotes that are not animals, plants, or fungi – many of which still exist today. That’s right: contemporary microscopic critters still “predate by perforation,” as it is technically known.
Two species, Vampyrella lateritia and V. pendula, have often been observed stabbing and drinking up algae innards; curiously, they both prefer different types of prey, and neither will consume the other’s favored meal. This new discovery means that this ghastly feeding mechanism has been around for nearly a billion years.
The arrows point to the vampiric puncture marks made in the fossilized phytoplankton. Susannah Porter
In terms of their oft-punctured prey, these ancient fossilized plankton may have not been entirely helpless. They were probably able to grow hardened cysts that could possibly have protected them from attack, just like their modern-day equivalents.
The evolution of the eukaryotes from 1.6 to 1 billion years ago was rather dull and slow; from this point onwards, their evolution appears to be far more nuanced and rapid. If future research reveals that these newfound predation puncture marks are not found on eukaryotes older than a billion years old, then it suggests that these defensive mechanisms rapidly evolved as a direct response to predation. In effect, these tiny vampires could have given the evolution of life on Earth a much needed rocket boost.
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