Lori Marino is a professor at Emory University in Atlanta who received a grant from the SETI Institute to start the Study of Life In The Universe (LITU) program. She gives the current status of her research in "The Evolution of Intelligence: An Integral Part of SETI and Astrobiology." Here are the opening paragraphs.
One of the fundamental questions of astrobiology is whether intelligence exists on other life-bearing planets. To study intelligence we must use quantifiable measures that are correlated with known characteristics of intelligence (problem solving, memory, etc.), amenable to comparisons across a wide range of organisms, and ideally, applicable to fossil as well as living organisms.
The Encephalization Quotient (EQ) is one such measure. EQ is a number that compares brain and body sizes across different species and tells us how large or small a species’ average brain size is for its average body size. Highly encephalized species have larger brains than expected for their body size and generally tend to be more intelligent. For instance, modern humans have an EQ of about 7. That means our brains are about seven times the size one would expect for an animal of our body size.
EQs are handy because they can be calculated for living organisms from brain size data and from fossil organisms from endocranial volume measurements. Furthermore, although encephalization is a direct measure of brain size it is correlated with increases in brain complexity. So, using EQ, we can capture a general estimate of intelligence (which is a function of brain size and complexity) across a wide range of species.
Fascinating, isn't? Marino and her colleague Dr. Daniel McShea from Duke University are now studying trends in cetacean brain evolution.
Cetaceans are highly encephalized, possessing EQs that range very close to that of humans and higher than that of other mammals. Yet cetaceans haven’t shared a common ancestor with primates for over 85 million years. As a result, their brains are very differently organized than primate brains. Therefore, cetaceans afford us the opportunity to examine a highly elaborated brain that has taken a very different evolutionary trajectory from our own.
Marino also studies other species. Here is a photograph from Lori Marino holding a dolphin brain (Credit: SETI Institute).
Here are some additional links about this research: another article about Marino from the SETI Institute, her homepage at Emory University and a list of her recent publications.
Source: Lori Marino, Emory University, for SETI Thursday at Space.com, August 20, 2003
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