恐龍卡第 0021 張，共 2 027 張

Acrotholus

名字的意思： “highest dome”1

吃：植物腫頭龍類白堊紀晚期

Acrotholus was a small, plant-eating dinosaur with a thick, bony dome on its head. It lived about 84 million years ago in what is now Canada. This dome might have been used for head-butting contests between rivals!1 2

生存年代

86 到 84 百萬年前4

白堊紀晚期

化石發現地

Fossils were found in the Milk River Formation in southern Alberta, Canada, near Writing-On-Stone Provincial Park.2 1

長度

1.8288 m (6 ft)3

體重

40 kg (88 lb)3 1 2

最高速度

時速約 44 公里（27 英里）

跑步, 估計值

牠生活在什麼時候？

三疊紀

侏羅紀

白堊紀

2 億 5200 萬年前20114566，小行星撞地球

牠有多大？

牠有多長？

牠有多重？

跟 2 隻狗一樣重

跟 4 隻家貓從鼻子接到尾巴一樣長跟 10 根香蕉頭尾相接一樣長跟 10 隻家貓一樣重跟 8 顆西瓜一樣重跟 2 個幼兒園小朋友一樣重跟 1 個小學生一樣重能在 8.2 秒內跑完 100 公尺（最快的人類要 9.6 秒）

Acrotholus 跟「你」比起來有多大？

只是在你的瀏覽器裡算算數學。什麼都不會被儲存或傳送出去。

牠有多快？

走路的人 時速約 5 公里 (3 mph)

騎腳踏車的小朋友 時速約 12 公里 (7 mph)

Acrotholus 時速約 44 公里 (27 mph)

一匹飛奔的馬 時速約 65 公里 (40 mph)

一隻獵豹 時速約 100 公里 (62 mph)

酷東西

趣味知識

Acrotholus is the oldest known pachycephalosaur from North America, and possibly the world.2

Its dome was very thick, up to 55 millimetres (about 2 inches) above the brain, which is almost half the total length of the dome.2

The dome was fully developed even though Acrotholus lived earlier than other pachycephalosaurs, showing that this feature evolved earlier than scientists thought.2

The name Acrotholus means 'highest dome' in Greek, referring to its thick skull roof.1

The species name audeti honors Roy Audet, a rancher who allowed scientists to dig on his land where the first skull was found.1 2

Acrotholus had a smooth dome without the bumps or grooves seen in some other pachycephalosaurs, which suggests the known fossils are from adults.2

Acrotholus 的 AI 繪圖 — 這是電腦根據科學家目前的知識，用 AI 畫出 Acrotholus 可能的樣子。這只是猜測：真正的動物可能長得不一樣，也沒有人知道牠真正的顏色。

你們都在問

關於 Acrotholus 最常被問的問題

?How big was Acrotholus?

Acrotholus was a small dinosaur, weighing 40 kg (88 lb) or less. Its skull dome was about 55 mm (2.2 in) thick.1 2

?What did Acrotholus eat?

Acrotholus was a plant-eating dinosaur, like other pachycephalosaurs.1

?Why did Acrotholus have a dome on its head?

The dome was probably used for head-butting contests between rivals, though scientists debate exactly how they used it.1

?When did Acrotholus live?

Acrotholus lived about 84 to 83.5 million years ago, during the Late Cretaceous period.1

迷思破解王

迷思： Some people think Acrotholus used its dome to butt heads like bighorn sheep.

真相： Scientists are not sure. The dome might have been for display or for fighting, but there is no direct evidence of head-butting in Acrotholus.1

給恐龍專家

學名: Acrotholus
命名者: Evans et al. 20134
類群: 腫頭龍類
科 / 演化支: Pachycephalosauridae4
分類: Ornithischia > Pachycephalosauria4
岩石的年代: 86 到 84 百萬年 (Santonian)4
岩層: Milk River4
國家: 加拿大4
化石紀錄: The Paleobiology Database 收錄 1 筆4
發現: The first fossil, a nearly complete skull dome, was found on Roy Audet's ranch in Alberta, Canada, and was named by David Evans and colleagues in 2013.1 2
仍有爭議: Scientists still debate whether the dome was used for fighting between males or for showing off to mates, since no complete skeleton has been found.1