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(連續圖片中斷,另外文章標題與圖上有所不同)

THE FOOTPRINTS OF LAETOLI  ~3,6 million years

Laetoli is a site in Tanzania, dated to the Plio-Pleistocene and famous for its hominin footprints, preserved in volcanic ash (Site G). The site of the Laetoli footprints is located 45 km south of Olduvai gorge. Professor Terry Harrison, a physical anthropologist at New York University, has continued research at the site since the late 1990s.

The footprint-bearing layers are Pliocene in age, dated by the K/Ar method to 3.6 million years ago.

A line of hominid fossil footprints, discovered in 1976 by Mary Leakey, is preserved in powdery volcanic ash from an eruption of the 20 km distant Sadiman Volcano. Soft rain cemented the ash-layer (15 cm thick) to tuff without destroying the prints. In time, they were covered by other ash deposits. The hominid prints were produced by three individuals, one walking in the footprints of the other, making the original tracks difficult to discover. As the tracks lead in the same direction, they might have been produced by a group -- but there is nothing else to support the common reconstruction of a nuclear family visiting the waterhole together.

The footprints demonstrate that the hominids walked upright habitually, as there are no knuckle-impressions. The feet do not have the mobile big toe of apes; instead, they have an arch (the bending of the sole of the foot) typical of modern humans. The hominids seem to have moved in a leisurely stroll. (click to see all the article on Wikipedia)

拉多里的足跡 ~36十萬年前

拉多里位於坦桑尼亞,有著著名的猿人足跡,在上新世-更新世時期,由火山灰保存下來。拉多里的足跡位於奧杜瓦伊峽谷以南45公里。泰瑞哈里森教授,紐約大學的體質人類學家,自90年代末期繼續該地的研究。其足跡所在之地層處於上新世時期,由鉀氬定年法判定出在36十萬年前。

此猿人化石足跡線,在1976年由瑪莉利基所發現,保存在從火山中噴發的粉狀火山灰中,距離賽迪曼火山20公里處。由軟雨凝結的灰層(15公分厚)並沒有摧毀足跡。最後,足跡被其他火山灰所覆蓋,得以保存下來。猿人足跡是由三個人踩出來,一個人是走在其他足跡中的,這使得原本的足跡難以被發現。由於痕跡歸於同一個方向,他們可能是但是沒有證據可證明,他們是一組核心家庭,一起往水坑過去。

此足跡表明了猿人直立行走時的習慣,因為並沒有趾結的壓痕。移動時並不像猿類會移動大腳趾,相反的,他們有現代人類的足弓(腳部唯一彎曲之處)形式。猿人們似乎悠閒地漫步著。

(拉多里無中文維基)

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