Lost Animals from 505 million years ago – A fun Christmas read!

Lost Animals from 505 million years ago

It’s Christmas Eve and I can’t bring myself to write a serious post so instead I am bringing to you a feature on some of my favourite animals from the Cambrian – a period of time 542 million years ago.


  • Anomalocaris – This is one of my favourite animals from the Cambrian era. It was a top predator that swam by undulating the flaps at the side of its body. The most prominent part of Anomalocaris is in my opinion the two tusks extending up to 7 inches from the head.  By examining holes in the fossils of potential prey items, scientists think these appendages were used to prise open Trilobites – a shelled animal, a bit like a crab (see below).


  • Trilobite – This is the prey of Anomalocaris (above). The Trilobites were incredibly diverse and came in 000’s of shapes and sizes (17,000 known species)!  They had many different ways of living from scavengers to predators and even forming symbiotic relationships with bacteria! Because of their amazing exoskeletons Trilobite fossils are incredibly sort after items fetching several thousands of pounds at auction.




  • Hallucigenia – this thing is just plain weird! A worm-like tube that walked on stilts! Specialists in the field were perplexed for a long time about the strange animal and even used to think it was the other way up! It has no resemblance to anything alive today, particularly because of the spines protruding from its back. We still don’t know for sure what these spines were made of, and their protection value – if any!


  • Opabinia – Like Anomalocaris, Opabinia had flabs on the side of its body that allowed it to control its movement. Unlike Anomalocaris, Opabinia has a proboscis (like an elephants trunk) which it probably used to pick up its food (like an elephant). Opabinia also had 5 eyes, and presumably a huge field of vision for locating prey (small soft-bodied creatures – not Trilobites or Hallucigenia) and predators (such as Anomalocaris).

There is no doubt that these animals are weird and fantastic for that weirdness. They represent a few of the many oddities natural selection can throw up. The fact that there are not 5 eyed predators or worms on stilts today, suggest these animals were evolutionary experiments, no longer suitable for the conditions we live in today. Or is it? We still know very little about the animals that live in the depth of the oceans. Could there be animals down there that resemble the animals that lived 550 million years ago?

For a better idea of what life was like as an animal 550 million years ago please watch the following short videos at:


Fantastic animations!

Merry Christmas and a Happy New Year!!

1 thought on “Lost Animals from 505 million years ago – A fun Christmas read!”

  1. Amazing how there are animals today in the sea that look the same as those.
    How they look is not that important, its their organs in side that have vertually not changed from the time they were created. When the inital design of a heart, blood, and basic organs was perfected, the creator (or evolver or what ever you believe) stuck with it.
    The fact that the whole respratory system had to work completely and perfectly from day 1 (or the animal would die) pretty much disproves any evolving of the system.

    Larry K


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