1 00:00:01,800 --> 00:00:04,320 Speaker 1: Welcome to brain Stuff, a production of I Heart Radio, 2 00:00:06,760 --> 00:00:11,160 Speaker 1: Hey brain Stuff Lauren vogelbam Here. It might seem like 3 00:00:11,240 --> 00:00:14,200 Speaker 1: geologists are just studying a bunch of old rocks, and 4 00:00:14,440 --> 00:00:17,759 Speaker 1: sometimes really old rocks, but the reality is that Earth 5 00:00:17,840 --> 00:00:20,960 Speaker 1: science researchers look back at the geologic record of our 6 00:00:21,000 --> 00:00:23,880 Speaker 1: planet to understand how we got here and what we 7 00:00:23,880 --> 00:00:26,319 Speaker 1: can expect next for Earth and the life that lives 8 00:00:26,320 --> 00:00:30,840 Speaker 1: here humans. Included in a study published in the journal 9 00:00:31,000 --> 00:00:36,200 Speaker 1: Geoscience Frontiers in November, researchers from New York and California 10 00:00:36,360 --> 00:00:39,480 Speaker 1: helped pinpoint an important fact about our planet that has 11 00:00:39,600 --> 00:00:43,839 Speaker 1: huge implications for us. Our Earth has a pulse, or 12 00:00:44,040 --> 00:00:48,080 Speaker 1: regular peaks of geologic activity. They identified the pulse in 13 00:00:48,159 --> 00:00:51,760 Speaker 1: part by looking at mass extinctions, something we obviously want 14 00:00:51,800 --> 00:00:53,960 Speaker 1: to know about since this is the only planet our 15 00:00:54,000 --> 00:00:58,520 Speaker 1: species currently calls home. The results of the study are 16 00:00:58,640 --> 00:01:01,880 Speaker 1: actually not new. They are just a more specific measurement 17 00:01:01,960 --> 00:01:04,960 Speaker 1: that tries to answer a question researchers have been asking 18 00:01:05,040 --> 00:01:08,520 Speaker 1: for nearly a century. A past research suggested that each 19 00:01:08,560 --> 00:01:11,679 Speaker 1: of Earth's pulses was between twenty six point four and 20 00:01:11,800 --> 00:01:15,440 Speaker 1: thirty million years apart. This study narrows that down further. 21 00:01:17,040 --> 00:01:20,320 Speaker 1: In this new study, the researchers used the latest technology 22 00:01:20,400 --> 00:01:23,119 Speaker 1: to analyze eighty nine geologic events in the past two 23 00:01:23,200 --> 00:01:26,319 Speaker 1: hundred and sixty million years of Earth's history, employing a 24 00:01:26,319 --> 00:01:29,959 Speaker 1: statistical technique called Fourier analysis to determine whether there was 25 00:01:29,959 --> 00:01:32,880 Speaker 1: any pattern in the frequency and consistency of the data. 26 00:01:34,319 --> 00:01:36,960 Speaker 1: When all the numbers were crunched, it turns out there 27 00:01:37,040 --> 00:01:40,040 Speaker 1: is a pattern, and it falls exactly within the range 28 00:01:40,040 --> 00:01:44,679 Speaker 1: proposed by previous researchers. Across these eighty nine events, which 29 00:01:44,720 --> 00:01:48,520 Speaker 1: the authors wrote, included marine and non marine extinctions, ocean 30 00:01:48,560 --> 00:01:53,160 Speaker 1: and oxic events, sea level oscillations, continental flood basalt eruptions, 31 00:01:53,200 --> 00:01:57,240 Speaker 1: and pulses of intraplate magnetism. They found ten clusters of 32 00:01:57,320 --> 00:02:01,760 Speaker 1: data points. These geological events ocurred roughly every twenty seven 33 00:02:01,840 --> 00:02:07,680 Speaker 1: point five million years. While it's certainly fascinating to have 34 00:02:07,800 --> 00:02:10,960 Speaker 1: more evidence that there's a consistent rhythm to cycles of 35 00:02:10,960 --> 00:02:14,640 Speaker 1: activity and life on Earth, the researchers in the study 36 00:02:14,840 --> 00:02:17,959 Speaker 1: aren't much closer to understanding why Earth has a pulse. 37 00:02:19,160 --> 00:02:23,120 Speaker 1: The authors do propose some ideas, though, One suggests that 38 00:02:23,280 --> 00:02:27,799 Speaker 1: internal forces within and on the planet Earth, including magma activity, 39 00:02:27,919 --> 00:02:32,120 Speaker 1: tectonic activity and climate change may explain the cyclical pattern. 40 00:02:33,440 --> 00:02:37,320 Speaker 1: Other ideas point to consistent changes in our planets orbital cycles, 41 00:02:37,400 --> 00:02:39,720 Speaker 1: and the fact that our solar system also has a 42 00:02:39,760 --> 00:02:43,160 Speaker 1: cyclical movement within the Milky Way galaxy roughly every thirty 43 00:02:43,160 --> 00:02:47,480 Speaker 1: million years. And yet another theory suggests that it may 44 00:02:47,520 --> 00:02:50,480 Speaker 1: have to do with dark matter in the universe. Several 45 00:02:50,520 --> 00:02:54,200 Speaker 1: researchers have proposed that increased dark matter may account for 46 00:02:54,240 --> 00:02:58,240 Speaker 1: increased astronomical activity like meteors and asteroids, as well as 47 00:02:58,320 --> 00:03:02,360 Speaker 1: volcanic activity on Earth. These can lead to mass extinction 48 00:03:02,400 --> 00:03:05,800 Speaker 1: events like those measured in the study. Those scientists still 49 00:03:05,840 --> 00:03:07,880 Speaker 1: have a lot to learn about dark matter before they 50 00:03:07,880 --> 00:03:10,360 Speaker 1: can begin to determine if this is a viable cause 51 00:03:10,440 --> 00:03:14,840 Speaker 1: for the pulse on our planet. No matter the cause, 52 00:03:15,120 --> 00:03:19,120 Speaker 1: this study suggests that the data is conclusive. Every twenty 53 00:03:19,160 --> 00:03:22,680 Speaker 1: seven point five million years, we can expect an uptick 54 00:03:22,760 --> 00:03:29,200 Speaker 1: in geologic activity, which often results in mass extinction. Don't worry, though, 55 00:03:29,320 --> 00:03:32,440 Speaker 1: because twenty seven point five million years is a very 56 00:03:32,520 --> 00:03:36,280 Speaker 1: long time for human kind on the scale of planetary history. 57 00:03:36,320 --> 00:03:39,360 Speaker 1: This time frame is brief, but our species is believed 58 00:03:39,400 --> 00:03:42,560 Speaker 1: to be only about two hundred thousand years old. That's 59 00:03:42,680 --> 00:03:46,960 Speaker 1: less than one percent of the time between pulses, and 60 00:03:47,120 --> 00:03:50,800 Speaker 1: we are between pulses right now. The study suggests that 61 00:03:50,840 --> 00:03:53,680 Speaker 1: the next pulse will be roughly twenty million years in 62 00:03:53,720 --> 00:03:58,520 Speaker 1: the future. For context, while dinosaurs, when extinct roughly sixty 63 00:03:58,520 --> 00:04:03,080 Speaker 1: five million years ago, commonly recognized modern animals like bears, pros, 64 00:04:03,160 --> 00:04:06,680 Speaker 1: and whales were only just emerging on the evolutionary timeline 65 00:04:06,880 --> 00:04:14,480 Speaker 1: twenty million years ago. Today's episode is based on the 66 00:04:14,560 --> 00:04:18,200 Speaker 1: article turns out Earth's pulse beats every twenty seven point 67 00:04:18,240 --> 00:04:21,279 Speaker 1: five million years, but why? On how stuff works dot Com, 68 00:04:21,400 --> 00:04:24,359 Speaker 1: written by Valerie Stymap. Brain Stuff is production of I 69 00:04:24,400 --> 00:04:26,560 Speaker 1: Heart Radio in partnership with how stuff Works dot Com, 70 00:04:26,600 --> 00:04:29,640 Speaker 1: and it's produced by Tyler Clang. For more podcasts from 71 00:04:29,640 --> 00:04:32,640 Speaker 1: my heart Radio, visit the I heart Radio app, Apple Podcasts, 72 00:04:32,720 --> 00:04:34,560 Speaker 1: or wherever you listen to your favorite shows.