Podcast: Play in new window | Download (Duration: 3:49 — 2.5MB) | Embed
We’re upside-down? In today’s rather short episode, we talk about the first creatures to have developed a centralized nervous system, though not a central nervous system as of yet. It was a simple worm like creature, with a nerve cord running along the length of its body, and an extra-large bundle of nerves toward its …
Podcast: Play in new window | Download (Duration: 7:35 — 5.2MB) | Embed
Electricity life and Frankensteinean experiments A stun gun works by passing electricity through your muscles, causing uncontrollable contractions. An electric eel, which is actually a type of fish, can do the same thing. There is a single celled creature that can conduct electrons from hydrogen sulfide in the soil, to oxygen dissolved in the water. …
Podcast: Play in new window | Download (Duration: 7:18 — 5.0MB) | Embed
side-stepping inheritance Darwin originally published “On the Origins of Species” in 1859. At the time, the mechanism of inheritance wasn’t well understood. Inheritance and the implication that lifeforms could change over time stood in contrast to the popular notion that God had created all things in perfect and unchanging forms. His theory only considered traits …
Podcast: Play in new window | Download (Duration: 8:49 — 6.0MB) | Embed
Why go multicellular? Bacteria are very successful. They’ve been around for billions of years, as compared to hundreds of millions for multicellular creatures. They have survived mass extinctions that wiped out things like the dinosaurs and others. Today, we look at salpingoeca rosetta, which can live as either a single celled creature, or in a …
Podcast: Play in new window | Download (Duration: 7:20 — 5.1MB) | Embed
The one become many, and the many are one How did life move from simple single celled forms, into more complex multicellular ones? In today’s episode, we talk about an experiment that induced that transition in the laboratory. Here’s a link to an article on the experiment. Multicellular Life Evolves in Laboratory And here’s a …
Podcast: Play in new window | Download (Duration: 7:31 — 5.2MB) | Embed
How to make a mind—part3 Take life, put it in the right environment, and give it between 3.5 and 4 billion years. We take the time to review what we’ve covered since “How to make a mind—part1,” episode 35; and “How to make a mind—part2,” episode 59. This sets us up nicely to talk about …
Podcast: Play in new window | Download (Duration: 10:38 — 7.3MB) | Embed
Death There are creatures that do not seem to have a natural limit on their life span. They only die when they are killed by accident or the action of sickness parasites and pathogens. Other creatures are apparently programmed to die at a given time, and under a given set of conditions. So why do …
Podcast: Play in new window | Download (Duration: 11:00 — 7.6MB) | Embed
Sex This episode turned out to be both long and hard. Feel free to snicker at this point. It was long because I couldn’t resist the numerical pun. To match this episode’s number with its subject, I had to squish together the development of eukaryotes with the development of sexual reproduction. Fortunately, they may both …
Podcast: Play in new window | Download (Duration: 7:17 — 4.9MB) | Embed
An environmental catastrophe Sometimes, a new species will come into being, and explode across the planet. The population increases drastically within a short time period as they learn to use new materials and new forms of energy. Sometimes, they produce material that is poisonous to forms of life that previously hadn’t encountered such substances. Many …
Podcast: Play in new window | Download (Duration: 9:12 — 6.2MB) | Embed
Don’t let the headlines fool you. Nobody knows how life started This is probably the least coherent episode to date. Though the precursors of life can apparently be produced by processes taking place anywhere from the deep sea to deep space, how to get from those starting chemicals to a living cell is still unknown. …