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ORIGINALLY PEOPLE thought that the long canines of saber-toothed cats were intended to pierce the thick skin of mammoths and were used to inflict gaping wounds. However, recent modeling suggests that repeated biting of struggling prey would result in breaking the saber-cats’ teeth, and that the fangs were used in a single neck bite on pinned prey, severing major blood vessels and quickly resulting in death.1 As the other two major groups of saber-tooth carnivores, Nimravidae and Barbourofelidae, have been extinct for millions of years, we will probably have to determine their diet based upon deduction. Fortunately the saber-toothed felids have been extinct for only tens of thousands of years, which is practically yesterday! We have some evidence of their diet in a cave that served as den for Homotherium and in the bones of Smilodon preserved in the La Brea tar pits.

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IN THE PAST few years there has been some acrimony regarding the division of the protostomes into Lophotrochozoa and Ecdysozoa. This decision split the annelids and the arthropods, and placed nematodes in with the arthropods. At its first proposal support for this tree was weak, but successive discoveries have strengthened it. Now the most detailed tree yet confirms this division, and clarifies other relationships.

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WHILE OUR species may be the most intelligent species on the planet at this point, our brains carry a lot of baggage from our evolutionary development that sometimes makes us irrational. This is not always a bad thing, but it requires that we be conscious of our weaknesses. We seem to be especially bad in understanding properly how the world works. Our intuitive understanding of physical processes is often wrong, and we can maintain this misunderstanding by failure to fully integrate observations that contradict it.1

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SINCE I STARTED this blog I have received an increasing number of hits from search engines. Unsurprisingly, one of the topics funneling people this way is the Nimravidae. My entry on the Dinictis skull replica found at Bone Clones has received the most hits overall since I started this blog. Unfortunately, there is not really much information about nimravids available without some digging, and very little on the open web. So here I will pull together everything I can currently get my hands on!

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I MENTIONED in a recent post that 75% of all of the types of mammals that have ever lived are now extinct. We have a tendency to think of extant organisms as all there is. We know dinosaurs once lived and are now extinct, but you’d be hard-pressed to get the average person to name one major extinct non-dinosaurian group. Yet we don’t have to look very far into our own past to find many of them.

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