Stethacanthus Altonensis Stethacanthus Was a Shark That Lived During Time: 300 Million the Jurassic Period Around 300 Million Years Ago

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Stethacanthus Altonensis Stethacanthus Was a Shark That Lived During Time: 300 Million the Jurassic Period Around 300 Million Years Ago

Crazy Creatures Stethacanthus altonensis Stethacanthus was a shark that lived during Time: 300 Million the Jurassic period around 300 million years ago. It is one of the most unusual sharks that years ago have ever lived, and is a mystery to scientists today! Period: Carboniferous Stethacanthus means “chest spine” after its most famous feature. It was around 70cm long, Shark with which means it was both a predator and prey for the many larger sharks around at the time. a Hat! Your task 1: Draw Stethacanthus! It had: A blunt nose A long shark body Two sets of short fins on the underside of its body Long whip like fins on its sides A huge crest of pointy spines on its back Your task 2: Male Stethacanthus had a unique tall crest of spines on it's back. Noone knows what it was used for. What do you think it could have been for? Creature Fact! Your task 3: Stethacanthus' crest was made of cartilage, not bone. Can you find out if sharks have bones like humans do? Stethacanthus closest What are the differences? living relatives are called the Ratfish and the Elephant fish! Your task 4: The long whip fins that Stethacanthus had are also a mystery! Why do you think a shark would have long thin fins like this? Your task 5: Male and Female Stethacanthus looked very different. Palaeontologists call this “dimorphism” meaning two shapes. Can you find another animal where the males and females are very different? You might want to look at animals with horns or manes to answer this one! Your task 6: Sharks have been around for millions of years and usually look very similar now to how they did in the past. Can you think of four reasons why Sharks are such good survivors? 1. 2. 3. 4. Research key words: Holocephali Cartilage Dimorphism CRAZYOMETER! How weird do you think this creature was? Boring! Yeah Ok A bit weird Really weird! Woah! By DiBgd - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=42204950 By Dmitry Bogdanov, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=3461298.

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Symmoriiform Sharks from the Pennsylvanian of Nebraska
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