Episode Details
Back to Episodes#169 – Life starts shape-shifting
Description
After life got a foothold on Earth, it immediately set about to filling the various emerging ecosystems with new organisms.

If you compressed the 3.7 billion year march of life on this planet down to 24 hours: earth comes into existence at midnight, the first fossils of life appear in the wee hours of the morning, the first multicellular life forms at dinner time, the first fish, land plants and amphibians by 10 pm, dinosaurs by 10:30, birds and mammals by 11:30 at night, and humans at midnight.
A lot happened during the last few hours of that day: what was life doing all morning and afternoon? We found out last week, in our conversation with Dr. Stephen Freeland, that it was building things using the complex macromolecules synthesized by non-living minerals around deep ocean hydrothermal vents, integrating together metabolic and genetic networks. Increasing the levels of complexity. Building genes, and sharing the information with neighboring bugs. Writing pages and pages of ideas. And then, right around the dinner hour on our metaphorical clock above, life hit the ground running. Combining, consolidating, integrating, experimenting …. producing plants, fish, amphibians, reptiles, insects, birds, mammals … and consciousness.
In this episode, we talk to Dr. Simon Conway Morris about that cosmic terraforming experiment, and some of the mechanisms involved. In particular, we talked quite a bit about convergence: different life forms on parallel evolutionary journeys landing on the same winning strategies again and again. I used the analogy of “reaching into the freezer” for solutions to physiological, environmental and evolutionary problems. That ‘freezer’ was the collective biotic genome that had been building up during the first two or three billion years … between “the wees hours of the morning” and the late afternoon on our metaphorical clock. Dr. Conway Morris wasn’t too comfortable with my ‘freezer’ analogy …. it sounded too much like Intelligent Design, and he is absolutely no fan of that ideology (nor am I or Scott). His preferred wording was to refer to the genome as being “seeded with inevitabilities”, which I think resonates perfectly with our overall theme of fine-tuning to produce life.
We also spent some ti