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Category Archives: elephants

Chinese elephant species went extinct only 3000 years ago

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And not 10,000 as it was believed until now.
Researchers have found that the elephant that existed in North China until c. 3000 years ago was not the Asian elephant (Elephas maximus) but another species that was believed extinct much earlier Paleoloxodon sp. or straight tusked elephant. The species or a closely related one went extinct in Europe some 30,000 years ago but survived in East Asia until… now we know that until the Iron Age in fact.
According to the BBC:


To investigate whether these mammals continued to live beyond the Pleistocene epoch and into the Holocene (the current geological epoch), the team re-examined fossilised elephant teeth discovered in Holocene layers of rock in North China during the 1900s.

And found them to be unmistakably Paleoloxodon, not Elephas.
Interestingly, the evidence was also in bronze art from the Xia, Shang and Zhou dynasties, which depicted elephants with two “fingers” in their trunks, like the African elephants but never the Asian ones.

Ref. Ji Li et al., The latest straight-tusked elephants (Palaeoloxodon)? “Wild elephants” lived 3000 years ago in North China. Quaternary International 2012. Pay per viewLINK [doi:10.1016/j.quaint.2011.10.039].

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Posted by on December 20, 2012 in Bronze Age, China, East Asia, elephants

 

Ivory worked in Andalusia 4800 years ago was from West Asia

The revolutionary ivory hoard
It has been reported today that workshops in the Chalcolithic (and Megalithic) site of Valencina de la Concepción (near Seville, Andalusia) used ivory imported from West Asia, belonging to tusks of the extinct Syrian (or also Assyrian) elephant (the westernmost variant of the Asian elephant, Elephas maximus). 
Until today it was generally believed (by default) that the ivory used in Chalcolithic crafting was from North Africa, however the (also extinct) North African elephant was a variant of the African species Loxodonta africana. 
While trade with Northern Europe (amber) was acknowledged as a matter of fact but was strongly supported by cultural elements (Megalithism), as well as by the unmistakably Nordic amber which washes to the beaches of the Baltic and German Sea, trade and cultural connections with the Eastern Mediterranean were considered speculative at best.
This discovery, which traces the first (indirect?) trade with West Asia to some 4800 years ago appears to demolish almost single-handedly the usual notions about Western European Chalcolithic (c. 3000-1800 BCE) by which contacts with the Eastern Mediterranean were considered speculative or even unlikely. There seems to be a glass bead in Eastern Iberia but nothing else that could support consistently contacts with anywhere East of Italy or Lybia. Only nearing the Bronze Age (which may begin c. 1850 BCE in the most developed parts of Iberia) such connections could be taken for granted (and yet mostly because of cultural rather than material imports). 
However the late Megalithic burial types of the Chalcolithic (tholos, artificial caves, etc.) which partly replace the classical dolmen in the areas we could well call more civilized (parts of Southern Iberia and Languedoc), has been argued in the past to be conceptual imports from the Eastern Mediterranean (places like Kurdistan and Cyprus, where tholoi were used first for housing apparently). But a time gap of a whole millennium (or more) made it all a bit hard to accept and the competing theory of the architectural concept of false dome (tholos) being invented twice became rather mainstream. 
The finding has been reported in the Acts of the Congress on Ivory and Elephants, which took place in Alicante and it’s also said to be published in the Journal of Archaeological Science (but I can’t find it so it may well be awaiting publication). The research has been carried by academics from the University of Huelva, the German Archaeological Institute and the Valencina Museum. 
 

Elephant hair density helps cooling

The low density of elephant hair has been demonstrated to help cooling:
Conor L. Myrvhold. What Is the Use of Elephant Hair? PLoS ONE 2012. Open access ··> LINK [doi:10.1371/journal.pone.0047018]

At low densities, hair has almost no effect on air flow and does not
trap an insulating air layer near the skin, but the extended hair acts
as a pin fin that increases thermal exchanges with the surrounding air.
Thus, as the hair density decreases from that of very furry animals, a
break-even point is reached where the hair function switches from an
insulator to a heat exchanger. This break-even point occurs at a density
of about 0.3 million hairs/m2 [26] for thick hair covers with creeping flow in between (recall that 1500 hairs/m2 is about the maximum density of elephants). For comparison, the hair density of the human head is about 2 million hairs/m2 (see Methods and Discussion S1).

These heat dispersal properties were already known for plants (leaf hair, cactus’ spines) but it is the first time to be demonstrated for an animal, more specifically a mammal like us. 
Figure 1. Pictures of elephant hair on the top of the back of an Asian elephant, (A) and an African elephant’s head (B).
The presence of hair on elephants was first noted by van Leeuwenhoek
[30]. Photos taken by Conor L. Myhrvold in the Woodland Park Zoo,
Seattle, Washington, from outside of the elephant enclosure, with
permission from the Zoo.
I searched online for hair density on human body (the question we all have in mind, right?) and I could only find a commercial reference (I’d appreciate a better one if you know one). Still it seems that the hair density on tights and legs (and therefore probably on most of the body) in humans is 50 hairs/cm², what translates as 0.5 million hairs/m², somewhat (but not a lot) above the threshold mentioned above.
I’d dare suspect that this means that human body hair (vellus) is for most people thermally neutral but then I wonder how it works with sweat, which is a key part of our tropical thermo-regulatory natural design. Elephants and plants do not sweat (although they do get wet on occasion), so it may well work somewhat different for them.
That seems to be an interesting challenge to explore.
 
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Posted by on November 27, 2012 in Anthropometry, biology, elephants, hair, human evolution