Khoisan mDNA and Africa’s Eve

There are a few things we know about the ‘original’ man of Africa. Genetics have traced our roots to a specific set of mDNA markers existing 200,000 years ago, a sort of genetic Eve for modern man. Archaeological evidence has traced the outpouring of man across the other continents to about 60,000 years ago (though this outpouring is still a theory only). A variety of methods and tactics have been employed to trace the relations of various groups of people from that point on, both through physical remains and modern biology, and through cultural markers such as language, tradition, history, and religion. But there’s still quite a bit we don’t know.

Quite a bit of what is left unknown is from that time span prior to the diaspora. The stone age began at some point before the diaspora. Such toolmaking has long been interpreted as the advent of civilization and a result of language, but the evidence is spotty at best. Conflicting theories of development (such as the idea, also largely unsupported, that Neanderthals had spoken language) are just as reasonable. Of particular interest are ideas of how one species may have replaced or interbred with another in a specific area.

Through studying the mDNA of Khoikhoi and San peoples, new theories are being posed for this early developmental time in Africa.  Maybe we were all meant to die out 70,000 years ago.  Maybe the speakers of that wonderful clicky language diverged from us genetically earlier than we’d previously thought.  Maybe they’re all closer to our genetic Eve mother and how we’re all ‘supposed’ to look.  Maybe after cheating death for thousands of years, our time as a species has come.  Maybe mDNA Eve is only one instance of the genetic change that was taking place across the globe all at once, and this whole diaspora idea is baloney.  Who knows?  But if we as a species were near extinction way back there in Africa, how would the world have developed without us?  It’s worth thinking about.

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Three fish, four fish…then no more fish

CNN’s blog arena recently published this little report on the counting abilities of the fishies.  Evidently, just like monkeys and one-year old children, mosquitofish have now been proven to have the ability to count to four.  Personally I find this vaguely disturbing.  I know that we all go through a sort of ‘fish stage’ in utero, but I didn’t realize that fish could have almost the same mental ability as monkeys, even in limited areas.  Considering the studies that have been done on fish and pain (which as far as I know, have not been conclusive either way yet), I would have expected the counting abilities of fish to be limited.  True, those with more developed brain areas related to optics probably have some way of categorizing different types of things, but I still would not have expected counting.

While it does seem to make sense that fish would have development equal to that of a very young child, at the same time, it makes me wonder a little more at our own development.  Who can truly remember the experience of being one year old, or even younger?  Despite the family anecdote of my younger sister describing her memory of the womb as ‘crowded’, I doubt the authenticity of any of these young memory claims.  Could we gain a glimpse of our own most basic selves through studying the experience of fish?  Could fish be made to expand their skills in to counting up to five, six, or beyond?  What are the implications of three versus many, and how do they relate in our minds to language, cognizance, or even civilization?

Your Brain on Autism

While the recent news spotlight has primarily focused on the legal implications of the Poling case, Fortune recently published this article detailing some of the current research in the area of autism and autism spectrum disorders, such as Aspergers. While it’s important to note that the implications of autism are far-reaching enough to merit publication in a business magazine dedicated to matters of finance, even more significant is the online rating of the article – after just five hours of publication, the article has been listed on the front web page of CNN. Perhaps it’s not surprising, as childhood cases continue to rise yearly.

Studies continue to attempt to link autism to its causes. Genetic predisposition is seen as a probable cause. Environmental factors are continually linked to various types of autism. New research shows that there are links to the rapidly mutating genes that allowed apes to cognitively develop into us over a short period of time. And throughout all this, those with high-functioning autism and Aspergers cry out for recognition as differently-thinking people, perhaps no more or less than neurotypicals.

What the studies and legalities that are developing fail to address are the true questions of life, the philosophies that remain largely unpondered in our daily lives. Who are we? Despite and perhaps because of our heritage and evolution, are we more or less than the sum of our genetics? What is autism, really, in the context of these questions? Do we gain or lose from them, and if so, how? If autism is often characterized by a lack or difference of language understanding and communication, do we lose from this lack, or can those with autism show us something outside of language and everyday communication that we have forgotten? If so, how do we best access this resource?

Ancient Americans Followed Giant Frog Across Land Bridge

Recently discovered are the bones of this 10-pound frog.  Interesting as the animal is as yet another example of current species as smaller than ancient ones, it comes with additional questions.  For example, the skeleton was found in Madagascar.  Though there are giant frogs in Africa, these particular bones are not related to those frogs – instead, they are related to much smaller South American varieties.  Quoi?  Scientist are hypothesizing that a) theories of continental shift and how closely the continents were at that time may be incorrect and/or that b) the froggies crossed from Africa to the Americas on a land bridge, possibly via Antarctica.

Some of you may be familiar with another land bridge theory from your elementary days involving Native Americans crossing via the Arctic from Asia.  It may surprise you that this theory has been partially debunked, though not thrown out in its entirety (yet).  In case you’ve forgotten, let me refresh your memory a bit.  The Bering Land Bridge model, or Beringia model, claims that land in the Arctic was uncovered during several ice ages (when the sea shrunk) and allowed for different species to travel and mix between the Asian and American continents.  Fair enough – there is adequate fossil and evolutionary evidence to authenticate this claim for a variety of species going in either direction.  The second part of the theory is what’s more contested.  It supposes that people crossed the land bridge from Asia around 12,000 BC, discovered and explored the only path between two giant glaciers that led to more fertile land at the south (sometimes only 10 meters in width), and spread Clovis culture throughout the Americas, all the way down to the southernmost tip of South America, all within a 1,000 year period.  It is a bit unlikely, but for a long time it was the most reasonable theory.

There was some questionable evidence of earlier colonization from archaeological sites, but no one really took it seriously until Mesa Verde was analyzed by a whole team of archeologists from different countries.  This site showed evidence of human habitation about 1,000 years earlier than the earliest Clovis settlement up in North America.  If the Clovis land bridge people handn’t even gotten to South America yet, who were these earlier inhabitants, where did they come form, and what happened to them?   Theories blossomed – they came across following the Bering Land Bridge in boats and then  followed the coastline of the Americas south much more quickly than the land travelers.  They came from Australia in boats via Antarctic islands.  Some of them came across the Atlantic.  Of course, some of these theories were more reasonable than others, but for various reasons, they all lacked one thing – evidence.

And that’s what we lack for Mr. Frog now.   Who knows?  His bones may teach us to rethink everything we know about geologic drift, or everything we think we know about the population of the Americas.  But especially in relation to younger children who soak up information like sponges, it should teach us at least one thing – give tehm wisdom rather than knowledge.  The specific details of history and science are not really relevant, and, given the current rate of new discoveries and refinements, will change in their lifetimes.  But a method of analyzing, questioning, and researching specific data for themselves – that will serve them well indefinitely.