Stories
Slash Boxes
Comments

SoylentNews is people

posted by martyb on Friday March 16 2018, @02:44PM   Printer-friendly
from the Moog-want-spear...-Gork-want-axe? dept.

Signs of symbolic behavior emerged at the dawn of our species in Africa

More than 320,000 years ago in the Rift Valley of Africa, some early innovators adopted a new technology: They eschewed the clunky, palm-size stone hand axes that their ancestors had used for more than a million years in favor of a sleek new toolkit. Like new generations of cellphones today, their Middle Stone Age (MSA) blades and points were smaller and more precise than the old so-called Acheulean hand axes and scrapers.

These toolmakers in the Olorgesailie Basin in Kenya chose as raw materials shiny black obsidian and white and green chert, rocks they had to get from distant sources or through trade networks. In another first, they chiseled red and black rocks, probably to use as crayons to color their bodies or spears—an early sign of symbolic behavior. "This is indicative of a gear change in behavior, toolmaking, and material culture," says evolutionary psychologist Robin Dunbar at the University of Oxford in the United Kingdom, who studies social networks.

A trio of papers released online in Science today documents this remarkable technological transition. Although other sites have yielded MSA tools, the new, securely dated chronology nudges the transition back by at least 20,000 years, matching when our species, Homo sapiens, is now thought to have emerged. By analyzing artifacts over time at one site, the papers also show that these behaviors developed as climate swings intensified, supporting the idea that environmental variability drove innovation.

Related:

Environmental dynamics during the onset of the Middle Stone Age in eastern Africa (DOI: 10.1126/science.aao2200) (DX)

Chronology of the Acheulean to Middle Stone Age transition in eastern Africa (DOI: 10.1126/science.aao2216) (DX)

Long-distance stone transport and pigment use in the earliest Middle Stone Age (DOI: 10.1126/science.aao2646) (DX)


Original Submission

 
This discussion has been archived. No new comments can be posted.
Display Options Threshold/Breakthrough Mark All as Read Mark All as Unread
The Fine Print: The following comments are owned by whoever posted them. We are not responsible for them in any way.
  • (Score: 2) by JoeMerchant on Saturday March 17 2018, @02:26AM

    by JoeMerchant (3937) on Saturday March 17 2018, @02:26AM (#653909)

    Yep, and not just on neurogenesis... Back when I was in school, they were teaching that when a nerve is cut, that's it, it's cut - never heals. I cut the sensory nerve that serves the outside of my right pinky finger in 1983, by 1993 near normal sensation was returning to it - and the neurosurgeon who was going to attempt a repair for me in 1983 knew that this was likely - but in 1984 my high school biology teachers were still teaching the "never recover" dogma. Now, that might not be neurogenesis, but actually just dendritic growth from the surviving neurons, but either way, it's basically back to 100% normal sensation now.

    I notice the most flip-flops in commercial "science" like the health ramifications of cholesterol in eggs, or fat from whatever, or artificial sweeteners. Then there's material safety like mercury in fillings, or arsenic in treated wood, or asbestos in insulation, or lead in gasoline and paint - those seem to stay mostly in one direction, and I'm sure some are overreactions, but with 7B people and growing, some percentage of the population probably has a problem with all those things and more.

    --
    🌻🌻 [google.com]
    Starting Score:    1  point
    Karma-Bonus Modifier   +1  

    Total Score:   2