Cache of Assault Weapons Discovered

Cosmo, Nearly 600 obsidian handaxes from 1.2 million years ago found in Ethiopia show early humans were smarter than we think

A trove of nearly 600 obsidian handaxes, dating back at least 1.2 million years, has been unearthed in Ethiopia, indicating the presence of a prehistoric “knapping workshop”.

Knapping is the technique used to create handaxes, which are often referred to as humanity’s “first great invention.”

Made by chipping shards off a piece of stone to make a sharp edge, handaxes were not attached to handles, but held in the hand. They have a distinctive teardrop or pear shape. They were made out of flint or, later, obsidian – a type of volcanic glass.

They call them stone "tools," but you and I know that if people were making them in those quantities, they used them as weapons, at least some of the time. If you were to meet a hyena over a kill, would prefer to be bare fisted, or to be carrying one of these?

The first handaxes in the palaeontological record date back to at least 1.5 million years ago and were found in Tanzania’s Olduvai Gorge. Handaxes are believed to have spread throughout Africa, south Asia, the Middle East and Europe around 500,000 years ago. They were still being made as recently as 40,000 years ago.

No other cultural artefact is known to have been made for such a long time.

Prior research has suggested that knapping workshops first cropped up in the prehistoric record in Europe several hundred thousand years ago – up to 774,000 years ago. The Ethiopian find nearly doubles the earlier estimates.

The researchers found 578 handaxes buried in sediment, all but three of which were made of obsidian. They were able to estimate the age of the tools by analysing the material around them.

The Wombat has Late Night With Rule 5 Sunday: Olivia Thirlby up on time an under budget at The Other McCain.

Wednesday Wetness, On the Rocks

The Wombat has both Rule 5 Sunday: Rabbit Season! posted at The Other McCain on time and under budget.

Is it Oil, or Is It Iron?

The Pennsylvania Department of  Environmental Protection would like to remind you all that not all scum is pollution. Oil Sheens - All That Glitters ... Isn't Necessarily Pollution

One of the most visible and obvious signs of water pollution is an oil sheen. Seeing a shiny, translucent reflection on a pond or lake just looks wrong - but did you know that not all sheens are the result of pollution? Here is what you should know about sheens, how to tell the difference between naturally occurring sheens and those that are the result of pollution, and what you should do if you discover a sheen caused by pollution.

A sheen is "an iridescent appearance on the surface of the water." The iridescent, lustrous appearance could be caused by a petroleum spill finding its way into the water - or the sheen could be a naturally occurring result of iron bacteria. Iron bacteria are small living organisms which naturally occur in soil, shallow groundwater, and surface waters and are harmless to the environment. Petroleum sheens on the other hand are harmful to the environment and should be reported to the Pennsylvania Department of Environmental Protection (DEP). But how can you tell the difference between the two and what should you do if you discover a sheen caused by pollution?

A very simple, yet very effective method to tell if an oil sheen is organic or the result of pollution, is to throw a rock into the sheen, or to break it apart with a stick. A bacterial sheen will typically break into small platelets when disturbed while a petroleum sheen will quickly reform. Another way to tell them apart is by smell. Natural sheens don't smell like petroleum.
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Please remember, the next time that you see an oily sheen on surface water, do the rock test to determine if the sheen is organic or the result of pollution and report all pollution sheens to DEP. 

I take from this that Pennsylvania has a substantial number of false reports of oil pollution caused by iron bacteria. The effect can be exacerbated by mines, like, say coal mines that Pennsylvania has in abundance, that can bleed acid mine waste loaded with the reduced iron that iron bacteria grow on, and cause the film, thus being a sign of pollution, albeit a different type of pollution than oil.

Several different pieces of ironstone on the beach today

However, the process is, in fact natural in many places, and if it goes on long enough can produce a well known form of iron ore, bog iron, which Vikings exploited as iron ore.

The process is quite common around here, usually in drainage ditches. Moreover, we have lots of evidence for the process from the past, in the form of ironstone, a form of sandstone commonly found in the ground, and washed up on our beaches.

A Trip to Agate Beach

One of Mary's grandkids, Anthony talked us into visiting Agate Beach at Patrick Point State Park, north of Trinidad California today. One of her other grandkids, Jasmine went along for the walk.

A look at the beach, which stretches up to Big Lagoon, from the top of the trail down.

 A fog bank was moving in and out all day, but we mostly had sun and blue sky, rare for the Redwood Coast

 A very strange berry

And down we go,

 The final steps down.

 Looking for bright, shiny agates in the coarse sand and gravel. There are many other interest rocks here, but since we are flying home we had to be selective.

 My first agate of the day, a small carnelian.

 Resting up for the climb back to the top. Left to right, Mary, Georgia, Anthony, and Jasmine.

Two different approaches to the initial ascent.

 A somber warning on the way up.

 Anthony's haul of 32

Our meager 5.