Monday, September 28, 2009

Simon Conway Morris - Lecture on Inevitability of Humans

While there are aspects about "inevitability" that are taken too literally (in that history is constrained because it has *already happened*) and that makes me alert for "woo-woo thinking", there is a good iTunes U lecture by Simon Conway Morris on the constrained design space in which evolution can occur. Conway Morris was the paleontologist that worked on the Burgess Shale fossils (originally collected by Charles Walcott in 1909). His findings provided ample fodder for Stephen Jay Gould to argue for the historical contingency of evolution in Wonderful Life. Ironically, in recent years Conway Morris has argued for something akin to the opposite of this stance: the convergence evolution. Here, he argues that that we are not here by chance: but are inevitable due to the strong structuring dimensions of the physical universe. This is explained in detail in his book Life's Solution: Inevitable Humans in a Lonely Universe.

I think the understanding of design constraints is an important issue, especially for archaeological applications of evolution. We need this concept in order to understand the space in which style can occur versus what is technologically necessary. For example, decoration can vary infinitely yet the vessel upon which it is placed may still have to serve as a fireproof container. Holes cut in the sides are part of that particular design space. Thus, we must be careful to construct classifications within those constraints in order to not confuse analogous similarity with homologous similarity. In many cases, the design space may be far smaller than one might think.

Conway Morris goes a little far here by arguing that the design space for life makes humans inevitable. There are certainly some dimensions of humans that are due to design constraints but distinguishing which are due to historical constrains (i.e., the environment of evolution) and which are due to design constraints (i.e., the chemico-physical dimensions that make us possible) are something to analyze, not to assume a priori.

The lecture is, nonetheless, a good one for thinking about evolution and issues of convergence.

Mannahatta: Manhattan of AD 1609

I've always been intrigued by the way in which past landscapes structure contemporary ones -- and how we can use our knowledge of shape of landscapes to explain why the environment we see today is the way it is. Cities are particularly interesting in this regard. The natural landscape often constrains and shapes the evolution of urban development and dictates the kinds of things that humans must cope with in order to do the business of being urban (i.e., transforming swamps to land, crossing rivers, knocking out hills, etc.). Perhaps the evidence of this interaction is nowhere better seen than in the shape and structure of Manhattan. The city has been so massively developed that one might think that isn't one shred of "natural" in the streets and buildings. Yet, that's not entirely true since the history of the growth of the city has had to embrace the natural features that long preceded Europeans -- streams, marshes, hills, geology, etc. Canal Street really was a canal at one point, built on top of a stream/wetland. Wall Street really is the site of an early historic wall, placed on a topographic high point when the island boasted a fort. And so on. An understanding of natural and historical world is required to understand Manhattan, as detailed in the amazing, insanely detailed, massive, chest crushing, Pulitzer Prize winning book "Gotham" by Burrows and Wallace.

Recently, the Wildlife Conservation Society has put together Mannahatta, a website dedicated to providing a way of understanding the natural heart of the island of Manhattan. It is pretty impressive. At the heart of the project is an interactive map of that shows the island as it was in AD 1609. The map allows you to look at a specific location and see where it stood in the Native American inhabited landscape of the early 17th century just prior to the arrival of Henry Hudson and other Europeans.


North American Luminescence Conference

I just signed up for the 6th biennial North American Luminescence Dating and Dosimetry Conference to be held in Seattle on October 22-24. ((To all my Seattle friends: I can't wait to see everyone.)) This year's conference is going to be hosted by Jim Feathers and his UW laboratory. Jim's work in luminescence sets the standard (extraordinarily high) for archaeological applications of luminescence and it will be worth the trip alone to hear what he and his lab are doing. As a bonus, the workshop features talks by luminescence experts doing work in geological applications -- such as high resolution dating of dune formation, etc. The cost is cheap: $28 for students, $55 for professionals. If you can make it, I recommend it.

Monday, September 14, 2009

More Ant Zombies

As reported in ScienceNews, an article in American Naturalist by Anderson et al (2009) documents the process by which fungus invades ants and turns them into zombies.


The original article in AN:

Andersen, S. B., et al. 2009. The life of a dead ant: The expression of an adaptive extended phenotype. American Naturalist, 174, (September): 424-433.

As an aside, Dretske has been working on the question that plagues everyone ... "How do you know you are not a zombie." Of course, this puzzles me daily. Required reading.