Bedrock: Earth's Earliest History

At long last, we finish the cliffhanger from Episode 52! Last time, I introduced one of the greatest debates in paleontology and geology. Are a few little triangles on the Greenland tundra Earth's oldest visible fossils , or just some funny-looking rocks? Today, we'll discuss both sides like a court case, laying out a decade of debate. This has been an episode Dylan has waited a long, long time to...

Good news : After six months, my girlfriend's hospital odyssey is wrapping up for now. Bad news : My visiting professorship at GVSU has finally ended, and the job hunt continues. For better and for worse, I have more time to return to the podcasts. Bedrock and Hometown Geology will alternate on Wednesdays. The Brisbane episode of Hometown Geology will air June 24 for Patreon subscribers, and Episo...

This brief update explains the long pause in episodes. A month ago, my girlfriend had a major, sudden hospital visit. The operation went smoothly, but there are many more hospital visits in the next few months. Episodes will return, but probably not until March. As always, thank you for your patience and well wishes! If you want to donate: One-off donations on Paypal Monthly donations on Patreon

Until now, all the clues for ancient life have been microscopic, beyond the realm of sight. Today, that begins to change. Ten years ago, a team of scientists showed the world a weird, lumpy rock that they claimed was the oldest microbial colony. Like a sci-fi movie, this specimen was found under melting ice in the high Arctic, unveiled from 3.7 billion years ago. But is it actually a fossil? Welco...

Here's a new monthly podcast that Dylan's releasing on Patreon! Hometown Geology focuses on cities/locations around the world, chosen by patrons. This pilot episode highlights Dylan's current hometown of Grand Rapids, MI, home of gypsum mines, coal forests, and mastodon skeletons. Want to hear next month's episode on Asuncion, Paraguay's capital, or to pick your own destination? Click here to sign...

This episode, we focus on just one special boulder from the Greenland tundra, a rock that might have Earth's oldest fossils. Over the past 10 years, scientists from around the world have used the latest technology to reveal this rock's secrets, including research published this year. What have they found? Extra Credit: Make a time capsule or play a record. Patreon for monthly donations One-off don...

Visit patreon.com/bedrockpodcast for bonus perks like new episodes, voting rights, and topic selection! P.S. Thanks to a bad cold, both my voice and the audio quality are not on par today. P.P.S. The cold has also delayed Episode 51, which will be up later this week.

Donate to support the show- anything is appreciated! Finally, 3.7 billion years ago, we reach some of the strongest evidence for life on Earth yet. It takes a while to find, and it only looks like a few dark crystals, but it's better than anything else we've seen so far. Along the way, we'll meet three scientists who helped define the quest for Earth's oldest fossils, including one of my old bosse...

In this casual chat, Dylan talks about the show's growth, the upcoming end of Season 2, a potential career shift to science communication, and other podcast recommendations. Thank you all for bringing this show to 50 episodes- here's to 50 more! Donate to support the show- anything is appreciated!

Many folks have claimed to find Earth's oldest fossils in the Greenland rocks, 3.7 billion years old. Before we meet and judge these contenders, we need to learn what counts as a fossil. This early in Earth history, nothing has any bones or teeth or shells, so researchers need to search for other clues. Today, I'll show you four ways to look for fossils in Earth's oldest rocks, including my person...

What is the hardest rock to make? Today's rock is very common in Earth's ancient past, and it should be everywhere today. However, it's nearly impossible to form in nature or the laboratory. Some experiments have tried for 32 years with no success! This rock is dolomite. Today, we address The Dolomite Problem, one of geology's longest-running mysteries. Along the way, we'll meet some smelly but he...

Donate to support the show- anything is appreciated! Today is a tale of two sisters: limestone and dolomite. Limestone is far more popular and well-behaved, one of the most common stones in nature and in architecture. Dolomite, though similar in many ways, is one of the most difficult rocks to make on Earth. Even dolomite’s name is a bone of contention. Today, we introduce both siblings to the sho...

What types of volcanoes were erupting 3.8 billion years ago? Today, we meet a new type of rock and a new type of volcano, far more powerful and dangerous than those we've met so far. The old volcano is long dead, but the scars it left behind can still be seen across the Greenland landscape. Along the way, we'll learn how different types of lavas are made, why a few rocks can float in water, and le...

What was Earth's mantle like 3.8 billion years ago, and how do we know? The mantle is a realm that humans have never visited, and examining it is only harder in the ancient past. Fortunately, the mantle sometimes gifts us with beautiful green rocks from the deep, souvenirs of an unknown underworld. Today, we learn how the mantle has changed over time, and its surprising connections to outer space....

What is the world's oldest slice of mantle, and how did it reach the surface? Today, we'll meet the first tangible piece of the world below the crust, a world humans still have not visited. Along the way, we'll meet an old mineral friend from Season 1, a researcher named Friend, and learn how diamonds can be a geologist's best friend when looking for slices of the mantle. Extra Credit: Clean your...

In 1971, two geologists traveled to the edge of Greenland's ice sheet. What they found were the oldest rocks known at the time, 3.8-3.7 billion years old. Shockingly, they were in decent condition, sparking a half-century of geology stories. Today we'll begin our tour of Isua, the final destination of Season 2. Along the way, we'll meet a Holocaust survivor who landed on top of the world, visit an...

Two months ago, I made an audience survey focusing on one topic: how would you like to support the show? Many folks answered, and here's what you said about donations, Patreon, ads, and merch. If you want to give your own opinion, take the survey here , put a comment below, or send a message to bedrock.mailbox@gmail.com. If you'd like to give a donation, you can click here - any amount is apprecia...

Nearly 30 years ago, one paper claimed to find the oldest evidence for life on Earth. How does that evidence hold up in 2025? Are these fossils or duds? Don’t panic, we’ll answer these questions to life, the universe, and everything in due time. Along the way, we’ll meet the most abundant mineral in the human body, an important fertilizer, and finish a trilogy of intense debates over a small Green...

In 1991, a mysterious, striped red and gray rock was discovered on a cold Greenland isle. Years later, this rock would rock the scientific world with multiple debates about the early oceans and life. What exactly is this rock, and why do we care? Stay tuned, and on the way, we’ll learn how scientists can officially argue with each other. Extra Credit: Eat something with peanut butter and chocolate...

How old is the oldest slice of Earth's seafloor? The answer is more contentious than you would think. Today, we visit one of the most debated locations in the show: a small island off the Greenland shore named Akilia. Everything about these rocks has been contested, and we'll meet three scientists who form cornerstones of the debates. Extra Credit: Watch something on an old CRT TV, or count tree r...

Earth’s crust is shattered into dozens of moving plates, but many other worlds operate very differently. What are some alternatives to plate tectonics? Today, we’ll compare tectonics on Earth with tectonics on other planets, through the lens of 3.9 billion-year-old rocks from Greenland. On the way, we’ll visit the westernmost town in the USA, visit one of our cosmic neighbors, and learn about the...

This season's final arc is set in Greenland. Let's start with the most common rocks in the region: what are they and what stories do they tell about the world 3.9 billion years ago? Along the way, we'll weave a tapestry of stone, boil some rocks, and learn a bit about Dylan's birthstone. Extra credit: try the Play-Doh experiment from this episode, or make some stone soup. Click here for the audien...

We're back! After nearly a year, Dylan has updates about his life and the future of the show. Please take the audience survey in the link below to let Dylan know how you'd like to support the show! Also, please check out the donate button if you like what you've heard so far. Click here for the audience survey! Donate to support the show- anything is appreciated!

Hi folks, If you’re a long-term listener, you know this show often takes long, multi-week breaks. This break has been much longer than normal, and will likely continue for a few months. What’s going on? Right now, I have one goal on my mind: to find a new, permanent job. My three-year contract at Grand Valley State University will end in April. I knew this going in, and it’s public information, so...

Hi folks! I've just been invited by my university to join a field trip to Iceland next week, one of the best spots in the world to study geology. This means there will be a slight hiccup in our programming. Episode 38 will drop early next week, while Episode 39 will hopefully drop the first week of August. If I have time and space, I might try some experimental episodes from Iceland itself, field...