11 November 2012

Human vs. chimps: What the "regulome" tells us about meat eating & bigger brains

Source: Greg Wray
The story about how humans evolved bigger brains begins some seven million years ago in central Africa. There, in a dense rainforest, there lived the last ancestor that we share with our closest living relatives. Our evolutionary paths diverged when the global climate changed and a new habitat took shape. While ancestors of chimpanzees retreated deeper into the rainforest to subsist on a diet mainly of fruits, our ancestors found themselves in on strange, new, dry grassland.

The savanna would mean a new way of life for our ancestors. They'd learn to use tools, communicate with each other using language, and work together to hunt animals for food. Based on fossil evidence and stable isotope data, our hominin ancestors shifted to a diet where meat was a principal energy source about two million years ago. It would be a major shift in diet that coincided with an increase in cranial capacity.

Now, scientists like Greg Wray, a professor of biology at Duke University, are beginning to better understand the genetic basis for the adaptation to eating meat and how it guided the development of our larger brains. During his plenary talk at the Council for the Advancement of Science Writing's (CASW) "New Horizons in Science 2012" annual conference in Durham, North Carolina, Wray said that the Encyclopedia of DNA Elements (ENCODE) project gave scientists like himself a "detailed street map" for seeking out the genetic changes that took place since the divergence of humans and chimpanzees over evolutionary time.

09 November 2012

Food is "star stuff"

Champagne supernova. Credit: Space Daily
"If you want to make an apple pie from scratch, you must first invent the universe."

When you eat a slice of apple pie, or any pie, or any food at all today, on Carl Sagan Day, it may be worthwhile to reflect on this quote, one of the beloved television series host's most famous from Cosmos: A Personal Voyage.

A look back at our origins is a good way to gain some perspective, amidst the accumulating scientific evidence, on how to understand our own biology and predicting ways in which we can keep our own healthy. Or, at least, that has been my conclusion. Starting at the beginning with the chemistry of life, our own evolution, and to that of our close cousins, then on to our current situation, and the future, this blog has explored all sorts of topics relating to diet and health in the past and forthcoming.

07 November 2012

Why lemurs get sick: A lesson for humans, too

Female blue-eyed lemur
What lessons can humans learn from our far distant prosimian primate cousins about living well and eating a healthy diet?

This was the question on my mind as I toured the Duke Lemur Center in Durham, North Carolina with colleagues attending Science Writers 2012. (Read Christie Wilcox’s full report about our tour over at Science Sushi on Scientific American.)

When I learned on the tour that lemurs were getting sick, I inquired further from our tour guides, education associate Chris Smith and education manager Niki Barnett. The thought of these adorable creatures—somehow related to me because of a common ancestor some 50 to 80 million years ago—suffering from the same types of chronic diseases as modern-day humans encouraged me to want to find out more about their care and treatment.