恐龍卡第 0019 張，共 2 027 張

Acristavus

名字的意思： “crestless grandfather”1

吃：植物鴨嘴龍類白堊紀晚期

Acristavus was a duck-billed dinosaur that lived about 80 million years ago. It had no crest on its head, which is unusual for its family. This plant-eater walked on two legs and could also move on all fours.1 2

生存年代

84 到 72 百萬年前5

白堊紀晚期

化石發現地

Montana and Utah, USA5

長度

8 到 9 m (26 到 30 ft)1

體重

2 公噸到 3 公噸 (4,400 到 6,600 lb)1

高度

2.5 到 3 m (8.2 到 9.8 ft)1

最高速度

時速約 26 公里（16 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？

牠有多高？

牠有多重？

跟 2 台汽車一樣重

跟 2 台汽車排成一排一樣長跟 50 根香蕉頭尾相接一樣長跟 150 隻狗一樣重跟 600 顆西瓜一樣重跟 4 整班小學生一樣重跟 7 隻北極熊一樣重能在 14 秒內跑完 100 公尺（最快的人類要 9.6 秒）

Acristavus 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)

Acristavus 時速約 26 公里 (16 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

Acristavus means 'crestless grandfather' because it is one of the oldest known duck-billed dinosaurs without a head crest.1

Its fossils were found in the Two Medicine Formation of Montana and the Wahweap Formation of Utah.5

Acristavus lived during the Campanian stage of the Late Cretaceous, about 83 to 72 million years ago.1

It belonged to a group called Brachylophosaurini, which includes other duck-billed dinosaurs like Brachylophosaurus.1

The type specimen, named MOR 1155, is a partial skeleton that helped scientists identify this species.5

Acristavus was a ground-dwelling herbivore that laid eggs, like all duck-billed dinosaurs.2

Acristavus 的 AI 繪圖 — 這是電腦根據科學家目前的知識，用 AI 畫出 Acristavus 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 Acristavus 最常被問的問題

?How big was Acristavus?

Scientists have not published a full size estimate yet, but as a hadrosaur it was probably around 8 to 9 metres (26 to 30 ft) long, about as long as a school bus.3 5

?Did Acristavus have a crest?

No. Acristavus is special because it had no crest or ornamentation on its skull, unlike most other duck-billed dinosaurs.3 4

?What did Acristavus eat?

Acristavus was a plant-eater (herbivore). It ate ferns, leaves and other plants that grew in its wet, seasonal habitat.5 3

?When did Acristavus live?

Acristavus lived about 79 to 81 million years ago, during the Campanian stage of the Late Cretaceous.3 5

給恐龍專家

學名: Acristavus
命名者: Gates et al. 20115
類群: 鴨嘴龍類
科 / 演化支: Hadrosauridae5
分類: Ornithischia > Ornithopoda > Iguanodontia > Hadrosauridae5
岩石的年代: 84 到 72 百萬年 (Campanian)5
岩層: Two Medicine, Wahweap5
國家: 美國5
化石紀錄: The Paleobiology Database 收錄 2 筆5
發現: Acristavus was named by Terry A. Gates, Jack Horner, and colleagues in 2011. The first fossils were found in Montana and Utah.1
仍有爭議: Scientists are not sure why Acristavus lacked a head crest while many other duck-billed dinosaurs had one.1