在非洲發(fā)現(xiàn)的數(shù)百個人類足跡化石揭示了古老的傳統(tǒng)
Hundreds of fossilized human footprints made between 5,760 and 19,100 years ago have been discovered in Africa, shedding light on what life was like in ancient communities, according to a new study. This represents the largest collection of fossilized footprints found in Africa to date.
一項新的研究發(fā)現(xiàn),在非洲發(fā)現(xiàn)了數(shù)百個人類足跡化石,這些腳印形成于5760年至19,100年前,揭示了古代社會的生活狀態(tài)。這是迄今為止在非洲發(fā)現(xiàn)的最大的化石腳印。
Researchers believed the 408 footprints, which form 17 different tracks, belonged to 14 adult females, two adult males and one juvenile male.
研究人員認為,這408個腳印形成17條不同的足跡,分別屬于14名成年女性、2名成年男性和1名少年男性。
"The footprints were made in a volcanic mudflow, and when that wet ash dried it hardened almost like concrete," said Kevin Hatala, study author and assistant professor of biology at Chatham University in Pennsylvania, in an email to CNN. "
“這些足跡是在火山泥流中形成的,當潮濕的火山灰變干后,它幾乎像混凝土一樣變硬,”研究報告的作者、賓夕法尼亞州查塔姆大學的生物學助理教授凱文·哈塔拉在給CNN的電子郵件中說。”
So the footprint surface itself is very resilient. But this surface was also buried by other layers of sediments, which helped to form protective layers that shielded the surface from the elements for thousands of years."
所以足跡表面本身是很有彈性的。但是,這個表面也被其他的沉積層所掩埋,這有助于形成保護層,使這個表面在幾千年的時間里不受自然因素的影響。”
The study published Thursday in the journal Scientific Reports.
這項研究周四發(fā)表在《科學報告》雜志上。
The footprints are located at the Engare Sero site, just south of Lake Natron, in northern Tanzania.
這些足跡位于坦桑尼亞北部納特隆湖以南的Engare Sero遺址。
"It is notable that the site, which preserves the most abundant assemblage of hominin footprints currently known from Africa, is within roughly 100 km [62 miles] of the site of Laetoli, which preserves the earliest confidently attributed hominin footprints," the authors wrote in the study.
研究報告的作者寫道:“值得注意的是,該遺址保存了迄今為止在非洲發(fā)現(xiàn)的最豐富的古人類足跡組合,距離拉多里遺址大約100公里(62英里),拉多里遺址保存了最早的古人類足跡。”
The site was discovered by members of the local Maasai community, and they shared this information with conservationists in 2008. About 56 human footprints were visible at the site in 2009 when the research team arrived thanks to natural erosion.
這個遺址是當?shù)伛R賽族人發(fā)現(xiàn)的,他們在2008年與自然資源保護主義者分享了這一信息。2009年,由于自然侵蝕作用,研究小組到達此地時,大約有56個人類腳印清晰可見。
Clues to ancient human behaviors
古代人類行為的線索
Fossilized footprints are unique because they can preserve potential evidence of human behaviors and activities.
足跡化石是獨一無二的,因為它們可以保存人類行為和活動的潛在證據(jù)。
"Footprints preserve amazing windows to the past, through which we can directly observe snapshots of people moving across their landscapes at specific moments in time," Hatala said.
哈塔拉說:“足跡保留了令人驚嘆過去之窗,通過這些窗口,我們可以直接觀察到人們在特定時刻穿越風景的快照。”。
"They can inform us of how fast people were moving, in which direction they were heading, how large their feet were and sometimes whether the people who made them may have been traveling in groups.
“它們可以告訴我們,人們移動的速度有多快,他們朝哪個方向移動,他們的腳有多大,有時還能告訴我們,留下它們(指足跡)的人是否曾結(jié)伴而行。”
With such rich details, we can directly observe behaviors in the fossil record, something that is very difficult to do with other forms of data."
有了這些豐富的細節(jié),我們可以直接觀察化石記錄中的行為,這是用其他形式的數(shù)據(jù)很難做到的。”
In order to get a sense of the information contained within the footprints, Hatala and his colleagues studied the sizes, spacings and orientations of the footprints. Spacing and orientation can share the speed and direction of someone's movement, while size can be used to estimate who made the footprints.
為了了解足跡所包含的信息,哈塔拉和他的同事們研究了腳印的大小、間隔和方向。間隔和方向可以了解一個人移動的速度和方向,而大小可以用來估計誰留下了腳印。
They were able to compare this data with that of footprints made by living humans to determine which footprints likely belonged to adults, juveniles, males and females, Hatala said.
哈塔拉說,他們能夠?qū)⑦@些數(shù)據(jù)與現(xiàn)存人類的足跡進行比較,從而確定哪些足跡可能屬于成年、未成年、男人和女人。
"With these estimates, we were able to gain a detailed picture of who was traveling across this surface, how they were moving and whether or not they may have been traveling together," he said.
“有了這些估計,我們能夠獲得關(guān)于誰在這個表面旅行的詳細圖片,他們是如何移動的,以及他們是否可能一起旅行,”他說。
This data was also compared with patterns of modern hunter-gatherer societies to understand the potential scenarios associated with these grouped footprints. And they realized that it was rare for large groups of adult females to travel together without adult males or children.
這些數(shù)據(jù)還與現(xiàn)代狩獵采集社會的模式進行了比較,以了解與這些分組足跡相關(guān)的潛在場景。他們意識到,一大群成年女性在沒有成年男性或孩子陪伴的情況下一起旅行是很罕見的。
"We hope that our study motivates future research that might help refine our abilities to use these amazing snapshots to reconstruct past behaviors," Hatala said. "At Engare Sero, our focus has shifted to site conservation.
哈塔拉說:“我們希望我們的研究能激發(fā)未來的研究,幫助我們完善使用這些令人驚嘆的快照來重現(xiàn)過去行為的能力。”“在Engare Sero遺址,我們的重點已經(jīng)轉(zhuǎn)移到場地保護。
Before we excavate any further, we want to work with the Tanzanian government to develop a long-term conservation plan, such that the site is still accessible for many generations to come."
在我們進一步挖掘之前,我們希望與坦桑尼亞政府合作,制定一個長期的保護計劃,這樣,這個遺址對未來的許多代人來說仍然是可以進入的。”