john hawks weblog

paleoanthropology, genetics and evolution

Crete again

Tue, 2010-02-16 09:21 -- John Hawks

I wrote about Crete twice last month ("Crete: Pleistocene port of call?", "More tools from Crete"). Now John Noble Wilford writes about Strasser and Panagopoulou's work: "On Crete, New Evidence of Very Ancient Mariners". The article reviews the finds, and then gives space to a bunch of speculations.

The exposed uplifted layers represent the sequence of geologic periods that have been well studied and dated, in some cases correlated to established dates of glacial and interglacial periods of the most recent ice age. In addition, the team analyzed the layer bearing the tools and determined that the soil had been on the surface 130,000 to 190,000 years ago.

Dr. Runnels said he considered this a minimum age for the tools themselves. They include not only quartz hand axes, but also cleavers and scrapers, all of which are in the Acheulean style. The tools could have been made millenniums before they became, as it were, frozen in time in the Cretan cliffs, the archaeologists said.

Dr. Runnels suggested that the tools could be at least twice as old as the geologic layers. Dr. Strasser said they could be as much as 700,000 years old. Further explorations are planned this summer.

Ancient artifacts may be exposed to the elements once again and then re-incorporated into more recent sedimentary contexts, a process called "reworking". It happens. But it's a stretch, unless there is some independent evidence that the tools and surrounding rocks bear signs of battering from water transport or other contextual evidence of reworking.

Going out and saying that the tools could be "as much as 700,000 years old" is just overreaching -- it's like they're trying to say this is comparable to the "earliest" evidence of watercraft. And you really have to stretch the dates to get there: Flores was apparently inhabited by 800,000 years ago.

At the end:

But archaeologists and experts on early nautical history said the discovery appeared to show that these surprisingly ancient mariners had craft sturdier and more reliable than rafts. They also must have had the cognitive ability to conceive and carry out repeated water crossing over great distances in order to establish sustainable populations producing an abundance of stone artifacts.

Maybe. Maybe not. What evidence is there that the crossings were "repeated"? Imagine what would serve...finding Crete-derived rocks in a mainland site would do it, or vice-versa. Any evidence of transport. I don't imagine we'll find any earlier human-introduced fauna, and a human-induced extinction might result from a single invasion, not a "sustained" record of multiple crossings.

I pointed to one such faunal turnover in my last Crete post, which would point to a human invasion in the mid-Middle Pleistocene. Parallel technical change with Greece or North Africa after this time would show multiple contacts -- but such evidence would suppose a long archaeological record that we don't yet have.

I just don't think it helps to speculate so freely. Sure, we might find things that surprise us. But the actual facts are surprising enough to justify funding much more work.

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