Expert: John J. Shea - 5/17/2004

Question
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Followup To
Question -
Hi John,

In "Consciousness Explained", Daniel Dennett says that our ancestors learned to cook root vegetables 1,500,000 years ago.

In a newspaper series on inventions, the British inventor James Dyson said that fire was discovered 1,400,000 years ago.

I'm inclined to go with Dennett, but can you throw any light on the issue?

Thanks for your time,

Rollo
Answer -
Rollo
The earliest putative evidence for fire is burnt bone from Swartkrans Member 3, which dates to shortly after 1.5 Million BP.  These sediments cannot be very precisely dated, so either 1.4 or 1.5 Million are equally likely.
Evidence for human use of fire is pretty sparse until around 0.5-0.2 Million years ago, though. There is a recent paper about early human fire use in the April 30 issue of Science that will be a good starting point for your search for references on the subject.
I know of no clear evidence for hominids or humans cooking vegetables until very recent contexts, ones younger than 10,000 years ago.  That they were doing so earlier seems reasonable, but it is an hypothesis we cannot test directly.
Cheers,
John Shea

PS: Apologies for the delay in my reply, I was called away from campus suddenly and did not have time to set my "unavailable" settings on the Allexperts website.

Hi John,

Thanks for the reply and don't worry about the delay. I'm very grateful.

I'm having the same problem, though. Your date for cooked meat is earlier than your date for man using fire.

They can't have been using microwaves.

Unless, of course, the meat was cooked in a forest fire.

I hadn't thought about the problem of archaeological evidence for the cooking of vegetables. Now I think about it. I'm surprised they have any evidence at all – the uneaten cooked vegetables I throw away don't look like they'll survive a year, let alone 10,000. Do you have any idea what sort of evidence has been found?

Hope you can help. Thanks in advance.

Rollo Metcalfe

Answer
Dear Rollo,
The evidence for plant foods is usually carbonized plant tissues (seeds, leaves, etc.).  There is a whole field devoted to the study of these kinds of remains, -archaeobotany (aka paleoethnobotany).  Carbon is very stable in most anthropologically-relevant sedimentary deposits, so one can recover quite a lot of plant macrofossils if one is careful and when preservation is good.  The problem, as you might expect, is telling plant remains that were created in the process of food preparation from those procured and burnt from other processes (use as fuel, bedding, materials for fibers).  For example, one excavation of a 700,000-year-old site in Israel produced charred seeds. Were these cooked, or just burnt while still attached to their stems as kindling, or were they plant matter that burnt naturally when fire swept across a former archaeological site?
The problem with tubers is a bit more complicated. We know that there were many rich tuber-bearing plants in the African habitats near where humans emerged.  All humans who now live in these areas exploit these tubers.  But when they began to do so remains a mystery because cooking these tubers does not necessarily carbonize them (think baked potatoes).
The most interesting papers about the roles of these tubers of which I am aware are those by Annie Vincent and Jean Sept. Richard Wrangham, Greg Laden and colleagues have some new papers out about this, but as far as I know, no direct evidence for tuber consumption in antiquity.
Best wishes,
John Shea