300m-year-old lizard found in Canada the earliest parental care in animals
The findings challenge the common scientific belief that parental care in animals is a more modern concept.
By AARON REICH
Amateur fossil hunter Brian Herbert was in for the shock of a lifetime when he discovered the remains of a lizard dating back 300 million years, and was even more shocked to find it protecting its young, Smithsonian Magazine reported.Finding the remains in the equally old stump of a tree in Cape Brenton, Nova Scotia, back in 2017, Herbert discovered the first known remains of an early land animal likely resembling a foot-long monitor lizard, which scientists have since dubbed Dendromaia unamakiensis – Greek for "tree" and "caring mother."The latter name is especially interesting, as the lizard was cradling the remains of what was likely its child.This news was astounding for scholars, and was the primary piece of evidence in a new paper published in the academic journal Nature Ecology & Evolution, which argued that the concept of parental care dates back hundreds of millions of years.This is stark contradiction to a commonly held scientific belief that parental care is a trait of modern animals.“We tend to think of animals in [this part of] the past as ‘primitive’ or ‘simple,’” says Jackie Lungmus, a vertebrate paleontologist at the University of Chicago uninvolved in the published paper, according to Smithsonian Magazine. “But they deserve more credit. Even back then… these animals were probably doing a lot of the things that animals still do today.”Despite being lizards, the mother and child may have more in common with humans genetically than with dinosaurs. According to Carleton University in Ottawa paleontologist Hillary Maddin, the animals were likely part of the synapsid lineage that evolved from reptiles into humans, The Independent reported.It is unclear why the two lizards died together. However, it is theorized that the area was a warmer swamp-like forest, and the adult had raised its child in a den it had built.However, some scholars are still hesitant to consider this an example of parental care, believing that the two may have been unrelated – maybe they were just short on space? The idea isn't unprecedented in the existing literature, according to American Museum of Natural History paleontologist Eva Hoffman, who added that until more examples of parent-child associations emerge in fossil finds, caution should be exercised.Another example theorized to prove parental care – the fossil of the synapsid Heleosaurus scholtzi and its child found in South Africa – only dated back 270 million years, a 40 million year difference.