恐龍卡第 0073 張，共 2 027 張

Alexornis

名字的意思： “Alex's ancestral bird”1

吃：肉早期鳥類白堊紀晚期

Alexornis was a tiny bird that lived during the Late Cretaceous in what is now Mexico. It was about the size of a sparrow and probably ate insects or other small animals. This bird is special because it belongs to a group called enantiornithines, which had a backwards shoulder joint compared to modern birds.1 3

生存年代

86 到 84 百萬年前3

白堊紀晚期

化石發現地

Southwest of El Rosario, Baja California, Mexico (La Bocana Roja Formation)3 1

體重

0.0356 kg (0 lb)1

最高速度

時速約 22 公里（14 英里）

飛行, 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？

牠有多重？

跟 0.5 根香蕉一樣重

比一隻家貓還輕能在 17 秒內飛越一整座足球場

Alexornis 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)

Alexornis 時速約 22 公里 (14 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

Alexornis is known from only one partial skeleton, which includes shoulder, wing, and leg bones, but no skull.1

It weighed only about 35.6 grams, which is roughly the same as a modern sparrow.1

When first discovered, scientists thought Alexornis was an ancestor of kingfishers and woodpeckers, but later studies showed it was an enantiornithine bird.1

Enantiornithines like Alexornis had a reversed joint between the shoulder blade and the collarbone, which confused early researchers.1

The fossil was discovered in 1971 and formally described in 1976 by paleontologist Pierce Brodkorb.1

Alexornis lived during the Santonian age of the Late Cretaceous, about 85 to 83 million years ago.3

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

?How big was Alexornis?

About the size of a sparrow, weighing roughly 35.6 grams.1

?What did Alexornis eat?

Scientists think it probably ate insects or other small animals, based on its small size and bird-like features.1

?Was Alexornis a dinosaur?

Alexornis was a bird, and birds are a type of dinosaur called avialan dinosaurs. So yes, it was a dinosaur.1

?When did Alexornis live?

It lived during the Late Cretaceous, about 85 to 83 million years ago.1

迷思破解王

迷思： Some people thought Alexornis was a modern bird ancestor.

真相： Actually, Alexornis is an enantiornithine, a group of ancient birds that went extinct with the dinosaurs.1

給恐龍專家

學名: Alexornis
命名者: Brodkorb 19763
類群: 早期鳥類
科 / 演化支: Alexornithidae3
分類: Theropoda > Avialae3
岩石的年代: 86 到 84 百萬年 (Santonian)3
岩層: La Bocana Roja3
國家: 墨西哥3
化石紀錄: The Paleobiology Database 收錄 1 筆3
發現: The only known fossil of Alexornis was found in 1971 near El Rosario, Baja California, Mexico. It was named and described in 1976 by Pierce Brodkorb, who thought it was an ancestor of modern kingfishers and woodpeckers.1 2
仍有爭議: Scientists are still unsure exactly how Alexornis is related to other enantiornithine birds, especially those from South America and Central Asia.1