Gar Fish
This is a very old fish that has been on Earth since the time of dinosaurs. It has a long snout and hard scales.
What is it?
A gar fish is a long, slender fish with a long snout full of sharp teeth. Its body is covered with hard, diamond-shaped scales. Gars are called "living fossils" because they have been around for more than 100 million years, since the Cretaceous period. They live in freshwater rivers, lakes, and swamps in North America.
How old?
Gar fish first appeared during the Cretaceous period, over 100 million years ago. That means they swam in the same waters as dinosaurs! They have changed very little since then.
What was it like?
Gars are ambush predators. They float near the surface, looking like a log, and then quickly snap up fish and other small animals with their long jaws. They can also breathe air using their swim bladder, which helps them survive in water with low oxygen.
Why does it matter?
Gars are important for understanding evolution. They show how some species can survive for millions of years without changing much. They also help keep freshwater ecosystems balanced by controlling prey populations.
Connections
Next to find
- Look for other living fossils like the coelacanth or horseshoe crab.
- Find a fish that has changed a lot over time and compare it to the gar.
- Visit a freshwater aquarium and spot a gar fish swimming.
雀鳝鱼
这是一种非常古老的鱼，从恐龙时代就存在了。它有一个长长的吻部和坚硬的鳞片。
这是什么？
雀鳝鱼是一种身体细长的鱼，有一个长长的吻部，里面长满了锋利的牙齿。它的身体覆盖着坚硬的菱形鳞片。雀鳝鱼被称为“活化石”，因为它们已经存在了超过1亿年，自白垩纪以来。它们生活在北美的淡水河流、湖泊和沼泽中。
有多古老？
雀鳝鱼最早出现在白垩纪，超过1亿年前。这意味着它们和恐龙在同一片水域中游动！从那时起，它们几乎没有变化。
它们是什么样的？
雀鳝鱼是伏击捕食者。它们漂浮在水面附近，看起来像一根木头，然后迅速用长颚咬住鱼类和其他小动物。它们还可以用鳔呼吸空气，这有助于它们在低氧水域中生存。
为什么重要？
雀鳝鱼对理解进化很重要。它们展示了一些物种如何能在数百万年里几乎不变地存活下来。它们还通过控制猎物数量来帮助维持淡水生态系统的平衡。
关联
下一步寻找
- 寻找其他活化石，比如腔棘鱼或鲎。
- 找一种变化很大的鱼，和雀鳝鱼比较。
- 参观淡水水族馆，观察雀鳝鱼游泳。