WEBVTT 1 00:00:00.600 --> 00:00:03.200 Welcome. This is Marsha for Radio I, and today I 2 00:00:03.200 --> 00:00:07.240 will be reading National Geographic magazine dated June twenty twenty five, 3 00:00:07.639 --> 00:00:11.240 which is donated by the publisher. As a reminder. RADIOI 4 00:00:11.359 --> 00:00:13.960 is a reading service intended for people who are blind 5 00:00:14.480 --> 00:00:16.920 or have other disabilities that make it difficult to read 6 00:00:16.960 --> 00:00:20.399 printed material. Please join me now for the continuation of 7 00:00:20.440 --> 00:00:25.000 the article I began last time, entitled Owases on the 8 00:00:25.079 --> 00:00:32.880 Brink by Tristan mc connell near Mahmad. The palms survive 9 00:00:33.039 --> 00:00:38.000 largely because farmers use ground water extracted with individual solar 10 00:00:38.000 --> 00:00:41.000 pumps to irrigate their plots. They are cheap to run 11 00:00:41.079 --> 00:00:44.159 and make extracting water easy, but they are a short 12 00:00:44.240 --> 00:00:47.960 term fix. The brackish ground water increases the salinity of 13 00:00:48.000 --> 00:00:51.719 the soil, making growing crops even more difficult, and pulling 14 00:00:51.759 --> 00:00:54.159 straight from the aquifer can put it out of reach 15 00:00:54.280 --> 00:00:57.560 of even the deepest palm tree roots. As long as 16 00:00:57.560 --> 00:01:00.679 people keep pumping ground water with solar they think there's 17 00:01:00.759 --> 00:01:04.159 no problem, says spy. But when you see solar you 18 00:01:04.159 --> 00:01:10.480 can very quickly kill the oasis. Abdul Kharim Banucci, a 19 00:01:10.640 --> 00:01:13.159 forty eight year old with a thick mustache, and dressed 20 00:01:13.159 --> 00:01:16.400 in a white tunic and turban. Has farmed in Mahmid 21 00:01:16.799 --> 00:01:18.879 all his life. When he was growing up, there were 22 00:01:18.920 --> 00:01:22.120 periods of drought that would decimate crops, he says, but 23 00:01:22.159 --> 00:01:25.680 the palms stayed strong. Now even they whither and date 24 00:01:25.760 --> 00:01:29.319 yields are falling. The palm cover on his acre plot 25 00:01:29.359 --> 00:01:32.280 is scant, and the fruit trees are gone. Unable to 26 00:01:32.319 --> 00:01:35.560 rely on the river or rain for irrigation, uses ground 27 00:01:35.599 --> 00:01:37.760 water pumped from his own well at the far end 28 00:01:37.760 --> 00:01:40.239 of his land, and every three years he must dig 29 00:01:40.280 --> 00:01:43.159 it deeper. In nineteen ninety six, a twenty three foot 30 00:01:43.200 --> 00:01:46.280 well was enough. Now it reaches to fifty two feet. 31 00:01:47.200 --> 00:01:50.640 It is in God's hands, BENAUI says, But as I 32 00:01:50.680 --> 00:01:52.840 see it, there is no future for farming here because 33 00:01:52.879 --> 00:01:56.560 of the water. In agriculture you always lose. He expects 34 00:01:56.640 --> 00:01:59.200 that eventually his three young sons, all of whom are 35 00:01:59.280 --> 00:02:03.799 under ten, will abandon farmining, abandoned farming and the oasis 36 00:02:04.480 --> 00:02:10.080 in a destructive feedback loop, migration pastins the oases surrender 37 00:02:10.199 --> 00:02:13.159 to the desert. The local population has fallen by a 38 00:02:13.199 --> 00:02:16.080 fifth in the past twenty years, and as mostly young 39 00:02:16.120 --> 00:02:19.719 people leave, it's harder for the aging population that remains 40 00:02:19.759 --> 00:02:23.759 to maintain the palm trees and irrigation channels. There's nothing 41 00:02:23.800 --> 00:02:26.599 to do here because there's no rain, so people emigrate, 42 00:02:26.719 --> 00:02:30.800 says sixty one year old farmer ab De Lai Lachbo, 43 00:02:31.639 --> 00:02:34.439 whose three sons have left. There is nobody around, just 44 00:02:34.599 --> 00:02:39.199 us old people. In his long white jalava and purple scarf, 45 00:02:39.479 --> 00:02:43.400 Laboch takes meat to the sand filled irrigation channels and 46 00:02:43.520 --> 00:02:47.159 sand covered fields nearby. There's nobody here to help us work, 47 00:02:47.199 --> 00:02:51.400 he says, shrugging. Neglected and abandoned plots. Let the desert in, 48 00:02:51.719 --> 00:02:53.800 and a few days of strong wind is all it 49 00:02:53.840 --> 00:02:56.800 takes to coat the earth with sand, starting the process 50 00:02:56.840 --> 00:03:01.240 of soiled degradation. As we walk around to Banao, one 51 00:03:01.319 --> 00:03:05.360 of Mohammad's satellite villages, Sabah tells me that of the 52 00:03:05.360 --> 00:03:08.639 two hundred families that used to live here, only five remain. 53 00:03:09.120 --> 00:03:11.240 The rest, he says, have seen their homes taken by 54 00:03:11.240 --> 00:03:14.199 the desert. They are no longer enough residence to clear 55 00:03:14.240 --> 00:03:18.719 the sand clogged alleys and passages, nor to maintain and 56 00:03:18.759 --> 00:03:22.439 repair the rammed earth walls of the Kassar, which are 57 00:03:22.479 --> 00:03:26.000 crumbling and collapsing like a sand castle in a rising tide. 58 00:03:26.680 --> 00:03:28.759 One of the few still living here is sixty eight 59 00:03:28.840 --> 00:03:33.280 year old the Ala'id Ilaghnoi, a thick set farmer who 60 00:03:33.319 --> 00:03:36.280 once who long ago seated the ground floor of his 61 00:03:36.400 --> 00:03:39.800 mud walled house to the desert. From his perch up stairs, 62 00:03:39.800 --> 00:03:42.599 he used the flashlight on his phone to peer at 63 00:03:42.639 --> 00:03:46.199 the sand filled hall below. If there is any chance 64 00:03:46.240 --> 00:03:50.400 of rescuing Mohammed and charting a path towards saving other 65 00:03:50.479 --> 00:03:53.599 oases across the world, it might come from a small 66 00:03:53.639 --> 00:03:56.439 two acre plot on the edge of town, where Sabai 67 00:03:56.479 --> 00:04:01.120 has constructed a laboratory of pilot projects aimed at holding 68 00:04:01.159 --> 00:04:05.039 back the desert and holding on to water. Acacia and 69 00:04:05.159 --> 00:04:10.080 tamarisk trees sprout from shallow, circular planters called water boxes 70 00:04:10.240 --> 00:04:14.080 that were designed by a Dutch horticulturist named Peter Hoff. 71 00:04:14.560 --> 00:04:17.720 These planters reduce the amount of water young saplings need 72 00:04:17.959 --> 00:04:21.360 and act as a barrier against the desert. For years, 73 00:04:21.399 --> 00:04:25.079 Spy has worked with a Dutch foundation called Sahara Roots, 74 00:04:25.120 --> 00:04:29.199 planting hundreds of trees around Mahid to strengthen what he 75 00:04:29.240 --> 00:04:32.519 calls the natural system. To stop the sand. He has 76 00:04:32.560 --> 00:04:36.759 also introduced pipes for drip fed irrigation, which snake across 77 00:04:36.839 --> 00:04:40.040 vegetable beds and use far less water than the traditional 78 00:04:40.040 --> 00:04:43.519 method of flood irrigation that ceased to make sense when 79 00:04:43.560 --> 00:04:47.319 the river stopped flowing. These solutions, though modest in scope, 80 00:04:47.560 --> 00:04:51.360 are all aimed at restoring and recalibrating the balance between 81 00:04:51.399 --> 00:04:54.000 the people of the oasis and the changing landscape in 82 00:04:54.040 --> 00:04:57.680 which they live. Take the solar pumps. Climate change has 83 00:04:57.720 --> 00:05:00.879 made them necessary, but when their private lyad owned, as 84 00:05:00.959 --> 00:05:04.160 most currently are, people take what they want regardless of 85 00:05:04.240 --> 00:05:09.040 the needs of others. Spy has been pushing local farmers 86 00:05:09.160 --> 00:05:12.959 and government agencies to reconsider how the pumps are used 87 00:05:13.319 --> 00:05:16.000 in nomadic culture. He says, you need to share everything. 88 00:05:16.480 --> 00:05:20.519 Thanks in part to Spy's lobbying, Morocco's National Agency for 89 00:05:20.560 --> 00:05:25.000 the Development of Oasis Zones and Argonne Trees is working 90 00:05:25.040 --> 00:05:29.120 to install communities solar pumps and wells to replace private 91 00:05:29.160 --> 00:05:32.560 ones in Mahmied and elsewhere, so that water can once 92 00:05:32.600 --> 00:05:38.079 again be managed communally and shared equitably. Of course, none 93 00:05:38.120 --> 00:05:40.959 of that will matter if the entire population of Mahmed 94 00:05:41.560 --> 00:05:45.680 leaves for better opportunities elsewhere, So in twenty sixteen, Spy 95 00:05:45.839 --> 00:05:50.560 co founded the Judour Sahira Music School with Thomas Duncan 96 00:05:50.720 --> 00:05:54.439 of the Playing for Change Foundation, a California nonprofit that 97 00:05:54.519 --> 00:05:58.040 uses music to bring communities together. We asked, what can 98 00:05:58.040 --> 00:06:00.519 you offer young people to make them stay so duncan. 99 00:06:01.040 --> 00:06:03.959 Their answer is to celebrate, share and preserve knowledge of 100 00:06:04.000 --> 00:06:08.240 the cultural traditions of the desert and the oasis. Children 101 00:06:08.319 --> 00:06:14.480 attend weekly music classes in the traditional Ahidos, Guana, rockba Akalal, 102 00:06:14.959 --> 00:06:18.639 and Chamra styles. The school has since given rise to 103 00:06:18.720 --> 00:06:23.240 the Zaman Festival, which features hundreds of musical artists from 104 00:06:23.240 --> 00:06:27.439 across the Sahara and attracts thousands of visitors. The school's 105 00:06:27.480 --> 00:06:31.600 new home, the Jodur Sahira Cultural Center, was completed last 106 00:06:31.680 --> 00:06:35.959 year and consists of two modern rammed earth buildings designed 107 00:06:36.079 --> 00:06:40.839 by Baraccan architect A Ziza Chahuni. One is a sunken 108 00:06:40.879 --> 00:06:44.439 amphitheater for musical performances, the other a classroom with a 109 00:06:44.480 --> 00:06:49.519 subterranean cistern. The two structures are connected by underground water pipes. 110 00:06:49.800 --> 00:06:53.639 Rainwater is collected and stored in the reservoir. Real resilience 111 00:06:53.680 --> 00:06:57.319 is saving every drop of rainwater, says by. A riad 112 00:06:57.439 --> 00:07:02.199 style building for visiting musicians is under construction near by. 113 00:07:02.439 --> 00:07:05.879 The idea was to revive traditional materials that completely make 114 00:07:05.959 --> 00:07:09.600 sense in the area, says Chooni, to build pride in 115 00:07:09.720 --> 00:07:13.720 traditional architecture, not to just copy the past, but be innovative. 116 00:07:14.279 --> 00:07:17.519 Sabai often talks about the importance of nomadic culture, the 117 00:07:17.600 --> 00:07:20.199 need to live within the constraints of nature and the 118 00:07:20.240 --> 00:07:24.279 desert's tough environment, to share resources as a community, to 119 00:07:24.399 --> 00:07:27.480 not waste anything. He says these old ways are key 120 00:07:27.560 --> 00:07:30.800 to the restoration and survival of the oasis in the 121 00:07:30.800 --> 00:07:34.800 face of climate change. Saba started as a tour operator 122 00:07:34.839 --> 00:07:39.319 before expanding into environmental and cultural activism. He still believes 123 00:07:39.319 --> 00:07:42.480 in the value of tourism to the oasis economy, but 124 00:07:42.639 --> 00:07:45.759 he wonders what kind of tourism the kind that builds 125 00:07:45.759 --> 00:07:49.439 with concrete, fills swimming pools with precious water, and tears 126 00:07:49.519 --> 00:07:53.199 up the dunes for gasoline fueled kicks, or something slower 127 00:07:53.199 --> 00:07:56.480 and simpler that treads more lightly on the land, exists 128 00:07:56.519 --> 00:07:59.199 in harmony with the landscape and draws on the rich 129 00:07:59.240 --> 00:08:03.279 culture and history of the oasis. One cold clear evening, 130 00:08:03.319 --> 00:08:06.480 he reclines against a thick poof on a hand woven 131 00:08:06.519 --> 00:08:09.759 carpet laid out by a fire. One of his guests 132 00:08:09.879 --> 00:08:14.040 is a taureg desert blues guitarists visiting the music school 133 00:08:14.120 --> 00:08:17.920 from Mauritania, who carefully serves tea poured from a small 134 00:08:17.959 --> 00:08:22.279 painted teapot. Teapot heated in the fire's embers. A waxing 135 00:08:22.360 --> 00:08:26.040 moon shines bright above, and a thick stand of date 136 00:08:26.079 --> 00:08:29.720 palms is silhouetted against the indigo sky. We have the stars, 137 00:08:29.759 --> 00:08:32.519 and a fire's spy says we are the luckiest people 138 00:08:32.559 --> 00:08:36.360 on earth. The oasis is fragile, it's future uncertain, but 139 00:08:36.600 --> 00:08:39.519 it is where Saby comes from and where he belongs, 140 00:08:39.600 --> 00:08:44.000 and he is determined to save it, the extraordinary oasis. 141 00:08:44.039 --> 00:08:48.320 For centuries, oases have been important cultural and ecological landmarks 142 00:08:48.320 --> 00:08:51.080 in Morocco, despite the fact that they receive fewer than 143 00:08:51.159 --> 00:08:54.440 ten inches of rain each year. They've persisted thanks to 144 00:08:54.480 --> 00:08:59.039 clever human engineering that takes advantage of a delicate ecological balance, 145 00:09:00.039 --> 00:09:03.480 opportune geography in the rain shadow of the Atlas Mountains, 146 00:09:03.720 --> 00:09:07.919 water flows in intermittent streams and collects, and low lying aquifers, 147 00:09:08.639 --> 00:09:12.840 protective palms, date palm trees, a keystone species, are planted 148 00:09:12.879 --> 00:09:16.399 to provide fruit and protect smaller plants from harsh sun, 149 00:09:16.559 --> 00:09:22.200 winds and sands. A fragile equilibrium under threat. Rising temperatures 150 00:09:22.200 --> 00:09:26.159 and changing rain patters due to climate change have exacerbated 151 00:09:26.559 --> 00:09:29.799 existing threats, which can have a ripple effect across the 152 00:09:29.840 --> 00:09:35.639 delicate oasis ecosystems. Drought less rainfall and increase drilling, lower 153 00:09:35.679 --> 00:09:40.919 water tables and rays, fire risks. Bayoude disease of fungal 154 00:09:41.200 --> 00:09:45.879 pathogen has killed significant portions of critical palm groves. Soil 155 00:09:46.000 --> 00:09:50.039 salinity salt from pumped ground water accumulates in the soil. 156 00:09:50.799 --> 00:09:57.519 Migration ecological stress causes community caretakers to flee desertification. Vacated 157 00:09:57.600 --> 00:10:03.519 land returns to desert, sand pollutes water fields and towns. Next, 158 00:10:03.879 --> 00:10:07.639 are we sure Pluto isn't a planet? Nearly twenty years 159 00:10:07.720 --> 00:10:10.879 since it was downgraded to a dwarf planet, Pluto's bona 160 00:10:10.960 --> 00:10:16.600 fides still spark debate by Eric Ault. After its discovery 161 00:10:16.600 --> 00:10:19.559 in nineteen thirty, Pluto was declared the ninth planet in 162 00:10:19.600 --> 00:10:23.480 our Solar system and quickly garnered attention not typically afforded 163 00:10:23.720 --> 00:10:26.679 to its galactic peers. This was thanks in part to 164 00:10:26.720 --> 00:10:31.039 the power of celebrity. The small, multi colored icy rock 165 00:10:31.399 --> 00:10:34.480 has long been associated with Bickey Mouse's pet dog, which 166 00:10:34.480 --> 00:10:39.120 which originally named Rover but most likely renamed after the 167 00:10:39.159 --> 00:10:42.879 planet in nineteen thirty one. Then in two thousand and five, 168 00:10:43.080 --> 00:10:46.559 Mike Brown, a professor of astronomy at Caltech, crashed the 169 00:10:46.600 --> 00:10:50.399 party upon discovering Eiras similar in size to Pluto and 170 00:10:50.480 --> 00:10:55.000 also in the Queper Belt, calling into question Pluto's classification. 171 00:10:55.639 --> 00:10:58.080 As a result, in two thousand and six, the International 172 00:10:58.200 --> 00:11:04.759 Astronomical Union AU voted to adopt new requirements for planetary status, 173 00:11:04.840 --> 00:11:07.240 kicking Pluto out of the club and into the newly 174 00:11:07.600 --> 00:11:12.559 defined category of dwarf planet. Brown expanded on his reasoning 175 00:11:12.639 --> 00:11:16.120 in his aptly titled memoir How I Killed Pluto and 176 00:11:16.200 --> 00:11:19.440 Why It Had It coming. In the years since, the 177 00:11:19.440 --> 00:11:23.559 worlds of science and pop culture have hotly debated Pluto's fate. 178 00:11:24.039 --> 00:11:28.440 Among Brown's good natured adversaries is Philip Metzger, a retired 179 00:11:28.480 --> 00:11:33.360 planetary physicist at Nassaus Kennedy Space Center, current associate scientist 180 00:11:33.440 --> 00:11:37.159 at the University of Central Florida, and avowed Pluto is 181 00:11:37.159 --> 00:11:40.720 a planet believer. To celebrate the ninety fifth anniversary of 182 00:11:40.720 --> 00:11:44.120 Pluto's discovery, we sat down with Brown and Metzger to 183 00:11:44.200 --> 00:11:48.840 get some clarity. Are Brown and his cohorts correct in 184 00:11:48.919 --> 00:11:53.039 reducing Pluto's significance and instead focusing on new discoveries like 185 00:11:53.080 --> 00:11:57.279 the still unconfirmed planet nine or dou Metzger and others 186 00:11:57.320 --> 00:12:00.720 have a solid argument for the triumphant return of everyone's 187 00:12:00.799 --> 00:12:04.759 favorite little planet. Mike, how did you arrive at your 188 00:12:04.759 --> 00:12:08.320 conclusion that Pluto isn't a planet? And Philip, how did 189 00:12:08.360 --> 00:12:10.080 you wind up on the other side of the fence? 190 00:12:10.840 --> 00:12:13.639 Mike Brown? Since I've been at Caltech, one of my 191 00:12:13.720 --> 00:12:16.000 main areas of interest has been the objects in the 192 00:12:16.000 --> 00:12:19.799 outer part of the Solar System and queeper belt, objects 193 00:12:20.080 --> 00:12:23.080 like Pluto. And one of the largest projects that I 194 00:12:23.120 --> 00:12:25.720 did back in the early two thousands was the first 195 00:12:25.799 --> 00:12:29.519 really wide scale search for other objects as large as Pluto, 196 00:12:29.919 --> 00:12:33.879 other dwarf planets before we called them dwarf planets, which 197 00:12:33.960 --> 00:12:38.159 by the way, is a stupid term. How so mb 198 00:12:38.600 --> 00:12:43.360 because it's unnecessarily confusing. Before the IAU made up that term, 199 00:12:43.399 --> 00:12:48.120 we use the word planetoid to describe these things that 200 00:12:48.159 --> 00:12:50.600 are small but round, and it's a much better word 201 00:12:50.639 --> 00:12:53.799 because it's not as confusing. The only reason that Pluto 202 00:12:53.879 --> 00:12:57.159 was called a dwarf planet after its planet status was 203 00:12:57.240 --> 00:13:00.440 revoked is because that was snuck in there by the 204 00:13:00.480 --> 00:13:05.279 pro Pluto people in hopes they could get then get 205 00:13:05.279 --> 00:13:08.559 a vote that dwarf planets are planets. The vote was 206 00:13:08.600 --> 00:13:12.039 then overwhelmingly rejected, but we are left with that stupid phrase. 207 00:13:12.399 --> 00:13:16.559 I blame the Pluto people for that, Philip Metzger. We 208 00:13:16.639 --> 00:13:19.000 would say that there are a lot of dwarf planets 209 00:13:19.360 --> 00:13:22.039 and that these dwarf planets are actually planets in the 210 00:13:22.159 --> 00:13:25.360 Queper Belt. But the thing is, we're not really arguing 211 00:13:25.440 --> 00:13:28.480 for Pluto to be reinstated because we think that the 212 00:13:28.559 --> 00:13:32.559 vote to downgrade it was irrelevant. The IAU didn't have 213 00:13:32.679 --> 00:13:35.399 a right to do that vote. They violated their own 214 00:13:35.440 --> 00:13:37.960 by laws when they did it. Our claim is that 215 00:13:38.000 --> 00:13:41.480 it never stopped being a planet because taxonomy is part 216 00:13:41.519 --> 00:13:44.440 of science, and the taxonomy that matters is the one 217 00:13:44.440 --> 00:13:48.279 that the scientists are using and finding useful, whereas the 218 00:13:48.320 --> 00:13:52.480 public's astrological based taxonomy is not useful for science. It 219 00:13:52.559 --> 00:13:56.000 doesn't align with any theories, and that's unfortunately the one 220 00:13:56.039 --> 00:13:59.720 that the i a U adopted well, let's start there. 221 00:14:00.120 --> 00:14:05.200 What other criteria for planet status p M. In two 222 00:14:05.240 --> 00:14:08.679 thousand and six, the IAU decided number one that a 223 00:14:08.720 --> 00:14:11.759 planet must orbit a star. Directly based on that, the 224 00:14:11.759 --> 00:14:14.200 Moon would not be a planet. It's what we call 225 00:14:14.240 --> 00:14:18.039 a secondary planet, whereas the Earth is a primary planet. 226 00:14:18.559 --> 00:14:20.759 The second thing they said is that a planet has 227 00:14:20.840 --> 00:14:23.399 to be large enough to pull itself into a round 228 00:14:23.399 --> 00:14:27.039 shape by its own gravity, what we call gravitational rounding. 229 00:14:27.480 --> 00:14:30.039 And then the third condition was, and this is the 230 00:14:30.039 --> 00:14:33.200 one designed to eliminate bodies like Pluto, it has to 231 00:14:33.240 --> 00:14:37.000 gravitationally dominate its orbit in order to clear the neighborhood 232 00:14:37.279 --> 00:14:40.960 of its own orbit from other bodies. They didn't define 233 00:14:41.000 --> 00:14:44.039 what that they meant by that, they disfigured people would 234 00:14:44.039 --> 00:14:47.000 make it more concrete. Later. You can argue that Earth 235 00:14:47.080 --> 00:14:49.720 is not a planet because the Earth doesn't clear out 236 00:14:49.759 --> 00:14:52.879 its own neighborhood. What they really meant was a planet 237 00:14:53.000 --> 00:14:57.080 has to be gravitationally dominant, according to some unknown metric 238 00:14:57.440 --> 00:15:02.480 that they hadn't created yet. Mike Brown. In nearly two thousands, 239 00:15:02.480 --> 00:15:05.320 digital cameras started to get much much better, and we 240 00:15:05.360 --> 00:15:07.720 could finally take pictures of the whole sky at once. 241 00:15:08.080 --> 00:15:12.200 We used that to discover these biggest, brightest dwarfest planets 242 00:15:12.360 --> 00:15:15.080 that are out there, including the one that really forced 243 00:15:15.120 --> 00:15:19.840 a discussion about Pluto. We discovered Eris, which is more 244 00:15:19.879 --> 00:15:22.519 massive than Pluto. And so suddenly something was going to 245 00:15:22.559 --> 00:15:24.759 have to give. You were either going to have to 246 00:15:24.840 --> 00:15:28.480 add new planets or subtract things that are no longer planets. 247 00:15:28.960 --> 00:15:31.799 If Pluto were discovered to day, nobody would say it 248 00:15:31.879 --> 00:15:35.080 was a planet. Are we too hung up on the 249 00:15:35.159 --> 00:15:37.879 number nine? Have we just all grown up with nine 250 00:15:37.919 --> 00:15:40.720 planets and the thought of either eight or infinite numbers 251 00:15:40.720 --> 00:15:45.559 of planets makes us uneasy? Mike Brown, No, there's no 252 00:15:45.720 --> 00:15:49.200 magic number. It's not that Pluto had to be subtracted. 253 00:15:49.440 --> 00:15:52.759 It's that astronomers were forced to acknowledge the reality that 254 00:15:52.799 --> 00:15:55.720 it didn't fit with what we know about planets now. 255 00:15:56.320 --> 00:15:59.200 The pro Pluto side tried to change the definition of 256 00:15:59.240 --> 00:16:01.840 a planet to be something. It's not because they were 257 00:16:01.840 --> 00:16:05.440 so desperate to keep Pluto a planet, but their definition 258 00:16:05.519 --> 00:16:08.799 would add two hundred more planets to our Solar system. 259 00:16:09.559 --> 00:16:12.360 The pro Pluto faction, by the way, is dominated by 260 00:16:12.399 --> 00:16:15.639 people who were involved in the nass omission to Pluto 261 00:16:16.080 --> 00:16:18.440 when they launched, Pluto was a planet. By the time 262 00:16:18.480 --> 00:16:23.679 they got there, it wasn't. Philip Metzger. It's cultural, it's 263 00:16:23.720 --> 00:16:26.600 not scientific. What else in nature is like that. I mean, 264 00:16:26.879 --> 00:16:29.320 we don't say there have to be only nine mountains, 265 00:16:29.399 --> 00:16:33.799 nine rivers, nine types of beetles. In elementary school, we 266 00:16:33.799 --> 00:16:36.759 were told that there are nine planets. That's it. Should 267 00:16:36.759 --> 00:16:42.879 it be taught as more of an evolving concept, Philip Metzger. Yeah, Unfortunately, 268 00:16:43.039 --> 00:16:45.320 when we're taught that there are only eight planets and 269 00:16:45.360 --> 00:16:48.679 these planets rain in their orbits, we're harkening back to 270 00:16:48.720 --> 00:16:53.360 the old geocentric concept. This outdated idea is just the simple, 271 00:16:53.759 --> 00:16:57.799 orderly monocentric and these planets are like gods. They rain 272 00:16:57.919 --> 00:17:01.960 in their orbit. We're arguing, need to teach that it's 273 00:17:01.960 --> 00:17:06.480 a dynamic cosmos. Things change, things evolve, planets can change 274 00:17:06.599 --> 00:17:10.839 their orbit. Scientists have hypothesized that there might be a 275 00:17:10.920 --> 00:17:14.839 replacement for Pluto, so called planet nine, but that's not 276 00:17:14.920 --> 00:17:19.000 just because they want a replacement for Pluto, right Mike Brown, 277 00:17:19.319 --> 00:17:21.720 Right now, the existence of planet nine is a very 278 00:17:21.759 --> 00:17:24.799 good hypothesis to explain a lot of things we're seeing 279 00:17:24.799 --> 00:17:28.039 out there that we have no other explanation for but 280 00:17:28.279 --> 00:17:30.359 until the day that we point a telescope at it 281 00:17:30.440 --> 00:17:33.319 and see it and say, ah, there it is. It 282 00:17:33.400 --> 00:17:38.519 is just the best hypothesis to explain these phenomena. In 283 00:17:38.559 --> 00:17:40.319 the end, Why do you think people have such an 284 00:17:40.359 --> 00:17:43.799 attachment to Pluto and a resistance to Planet nine or 285 00:17:43.839 --> 00:17:49.319 other possible replacements, Philip Metzger. All I can say is 286 00:17:49.359 --> 00:17:52.920 when the New Horizons spacecraft flew by Pluto, it was amazing. 287 00:17:53.000 --> 00:17:55.680 I was at Johns Hopkins University where they had the 288 00:17:55.680 --> 00:17:58.160 control center when they put up the pictures for the 289 00:17:58.200 --> 00:18:02.359 first time. It was just so bread taking and geologically diverse. 290 00:18:02.720 --> 00:18:05.200 I mean, there are mountains as tall as the Rocky Mountains, 291 00:18:05.480 --> 00:18:08.960 and there are glaciers flowing, and there's a layered atmosphere, 292 00:18:09.000 --> 00:18:13.319 and there's probably an underground ocean, and there's organic material 293 00:18:13.759 --> 00:18:16.160 the building blocks of life all over the surface of 294 00:18:16.200 --> 00:18:19.359 the planet. Not only is Pluto a planet, but it's 295 00:18:19.400 --> 00:18:23.279 also more of another Earth than any other. It's the 296 00:18:23.319 --> 00:18:28.160 most planet like planet. Mike Brown, I have an attachment 297 00:18:28.160 --> 00:18:30.480 to Pluto. When I was growing up. It was this weird, 298 00:18:30.559 --> 00:18:33.119 mysterious thing at the edge of the Solar System. Who 299 00:18:33.160 --> 00:18:35.559 would not think it's kind of weird and small and cute, 300 00:18:35.960 --> 00:18:38.480 and now we've seen pictures of it. It is kind 301 00:18:38.480 --> 00:18:42.400 of a cool looking thing. It's a cool place. Next, 302 00:18:42.599 --> 00:18:46.400 what can we learn from the genius of beavers? By 303 00:18:46.640 --> 00:18:51.440 Ben Goldfarb. First there were peals, then pests, but now 304 00:18:51.480 --> 00:18:56.000 they are emerging as something else, climate heroes. The East 305 00:18:56.519 --> 00:19:01.000 Troublesome Fire erupt it on October twenty u Wine twenty twenty. 306 00:19:01.960 --> 00:19:05.319 Whipped by strong winds and fueled by drought parched forests, 307 00:19:05.640 --> 00:19:09.000 the fire roared through northern Colorado's spruce and fir woods. 308 00:19:09.240 --> 00:19:12.799 It leaped roads and rivers and the Continental Divide, scaling 309 00:19:12.839 --> 00:19:16.960 mountain passes above tree line. It incinerated historic buildings in 310 00:19:17.079 --> 00:19:20.880 Rocky Mountain National Park and homes in Grand County, killing 311 00:19:20.920 --> 00:19:25.400 two people. Ultimately, it torched nearly two hundred thousand acres, 312 00:19:25.400 --> 00:19:29.359 making it the second largest fire in Colorado's history. In 313 00:19:29.400 --> 00:19:31.960 the end, just about the only thing the East Troublesome 314 00:19:32.039 --> 00:19:37.119 didn't consume was beaver ponds. This was not entirely surprising. Beavers, 315 00:19:37.160 --> 00:19:40.039 of course built dams that store water, and water, as 316 00:19:40.079 --> 00:19:43.039 you may know, doesn't burn. But the benefit the semi 317 00:19:43.079 --> 00:19:46.720 aquatic rodents provide goes further than that. In a study 318 00:19:46.759 --> 00:19:50.680 published weeks before the East Troublesome blew up, Emily Fairfax 319 00:19:50.799 --> 00:19:55.000 and eco hydrologists now at the University of Minnesota, found 320 00:19:55.119 --> 00:19:59.000 that beaver ponds and canals irrigate the landscape so thoroughly 321 00:19:59.079 --> 00:20:04.440 that they turned crisp of flammable plants into lush, fireproof ones, 322 00:20:04.839 --> 00:20:08.839 forming green refuges in which wildlife and livestock can retreat. 323 00:20:09.279 --> 00:20:12.640 In a nod to another firefighting icon, Fairfax and her 324 00:20:12.640 --> 00:20:17.480 co author titled their paper Smokey the Beaver. Fairfax studied 325 00:20:17.480 --> 00:20:21.880 five fires between two thousand twenty eighteen to reach her conclusions, 326 00:20:22.160 --> 00:20:24.759 but the East Troublesome was far bigger than most of 327 00:20:24.839 --> 00:20:28.240 those places, and a harbinger of the kind of conflagration 328 00:20:28.680 --> 00:20:31.880 worth seeing more and more. Although fire has long been 329 00:20:31.920 --> 00:20:35.720 a natural force of regeneration on North American landscapes, the 330 00:20:35.720 --> 00:20:39.640 so called megafires that plague the ever drier West are 331 00:20:39.680 --> 00:20:44.160 a different matter, stoked by climate change into exclusive infernos 332 00:20:44.440 --> 00:20:48.559 that burn so big and hot that ecosystems don't always 333 00:20:48.720 --> 00:20:53.440 readily recover. Fairfax doubted whether beavers could still fireproof large 334 00:20:53.519 --> 00:20:57.119 tracts of the landscape under those conditions, But when she 335 00:20:57.240 --> 00:21:00.759 visited the charred forests left behind by the Ear Troublesome 336 00:21:01.160 --> 00:21:04.920 and one other megafire, she discovered that the oases beavers 337 00:21:05.000 --> 00:21:10.000 created with their ponds had endured. There are entire rivers 338 00:21:10.000 --> 00:21:12.880 that are basically unaffected by the fire because it's just 339 00:21:12.960 --> 00:21:15.920 beaver dams the whole way, she said. Everything is full 340 00:21:15.920 --> 00:21:18.559 of life. The reeds are growing, the pine needles are 341 00:21:18.559 --> 00:21:22.359 still on the trees. The ponds aren't merely helpful before 342 00:21:22.400 --> 00:21:26.519 a fire. They can also protect ecosystems from the effects 343 00:21:26.759 --> 00:21:29.799 that come right after a blaze, capturing the ash and 344 00:21:29.880 --> 00:21:33.519 debris that run off hill slopes and shielding downstream fish 345 00:21:33.599 --> 00:21:36.960 and drinking water. In a twenty twenty four paper describing 346 00:21:37.000 --> 00:21:42.119 their findings, Fairfax and her collaborators concluded that beavers can 347 00:21:42.160 --> 00:21:46.279 be part of a comprehensive fire mitigation strategy. Once hunted 348 00:21:46.319 --> 00:21:49.319 to near extinction for their pelts and later villainized as 349 00:21:49.359 --> 00:21:53.200 a nuisance, beavers have rebounded. There are now ten to 350 00:21:53.240 --> 00:21:57.559 fifteen million swimming and waddling across most of North America, 351 00:21:57.960 --> 00:22:00.960 and they're ready for their third act us in an 352 00:22:01.039 --> 00:22:06.160 improbable roll. Ecological saviors to a climate change ravaged world, 353 00:22:06.400 --> 00:22:09.680 and fire mitigation is just the start. By building dams 354 00:22:09.720 --> 00:22:13.960 that slow stream flow, they create reservoirs that help combat drought. 355 00:22:14.279 --> 00:22:19.359 By sculpting wetlands, they furnish habitat for other animals. Nowhere 356 00:22:19.440 --> 00:22:22.119 is their return more necessary than in the climate stressed 357 00:22:22.160 --> 00:22:26.480 American West, where beaver restoration is unfolding to some extent 358 00:22:26.640 --> 00:22:30.240 in every state. But beaver's tireless meddlers with a penchant 359 00:22:30.279 --> 00:22:35.079 for running a foul of human infrastructure aren't yet universally welcome. 360 00:22:35.680 --> 00:22:39.640 The San Pedro River snakes across Arizona's border with Mexico 361 00:22:40.039 --> 00:22:44.519 through the sun blasted Sonoran Desert, though the arid land 362 00:22:44.519 --> 00:22:48.000 seems better suited for rattlesnakes than for semi aquatic rodents. 363 00:22:48.359 --> 00:22:51.559 Frontiersmen once knew the San Pedro as the Beaver River, 364 00:22:52.079 --> 00:22:56.200 before nineteenth century trappers stripped it clean anywhere there were 365 00:22:56.279 --> 00:23:01.559 perennial waters there, or probably beaver's lisas by Spypeck, the 366 00:23:01.720 --> 00:23:05.200 director of a non prophet called the Watershed Management Group, 367 00:23:05.559 --> 00:23:08.720 told me one fall day along the San Pedro's cobble 368 00:23:08.799 --> 00:23:12.319 strewn banks in nineteen ninety nine, in hopes of enhancing 369 00:23:12.359 --> 00:23:16.319 the area's Wildlife habitat the Federal Bureau of Land Management 370 00:23:16.640 --> 00:23:21.079 restocked the San Pedro with sixteen beavers, whose offspring dispersed 371 00:23:21.119 --> 00:23:26.160 throughout the river, including into Mexico. Since twenty twenty twenty, Spypeck, 372 00:23:26.519 --> 00:23:30.440 along with Mexican biologists and legions of volunteers, has been 373 00:23:30.519 --> 00:23:34.079 scouring the river to estimate their population. I joined her 374 00:23:34.119 --> 00:23:37.160 team for a day of surveying the San Pedro's shady 375 00:23:37.240 --> 00:23:43.039 cottonwood galleries for beavers. Shue marks, treks and lodges. Along 376 00:23:43.079 --> 00:23:46.279 the trunk of one downed cottonwood, beavers had chiseled away 377 00:23:46.319 --> 00:23:50.039 the bark to expose cream colored heartwood and whittled limbs 378 00:23:50.039 --> 00:23:53.799 to blunt points. Pale chips littered the bank. They were 379 00:23:53.839 --> 00:23:57.119 probably here within the last few weeks. Spypeck half whispered 380 00:23:57.599 --> 00:24:01.400 cezy to emphaths empathize with beaver. Like many of us, 381 00:24:01.400 --> 00:24:04.640 they live in nuclear families. A typical colony consists of 382 00:24:04.680 --> 00:24:07.880 a breeding pear and their offspring, which stick around until 383 00:24:07.920 --> 00:24:11.559 the age of two. On land, beavers are clumsy morsels 384 00:24:11.559 --> 00:24:15.960 for cougars, wolves, and bears, but their balletic swimmers endowed 385 00:24:16.000 --> 00:24:22.319 with transparent eyelids and webbed hind feet, Their keratins, scaled 386 00:24:22.480 --> 00:24:26.200 tails serve as fat storage units, and rudders. Their iron 387 00:24:26.279 --> 00:24:29.160 reinforced teeth scrape away the inner bark that provides the 388 00:24:29.200 --> 00:24:33.319 bulk of their herbivorous diet. By building dams and filling 389 00:24:33.359 --> 00:24:37.279 ponds around their woody lodges, beavers expand and defend their 390 00:24:37.279 --> 00:24:42.839 aquatic domains like feudal lords with moats around castles. Like humans, too, 391 00:24:42.960 --> 00:24:46.480 beavers are survivors, just as Homo sapiens are the last 392 00:24:46.480 --> 00:24:50.200 and a long line of hominins. The world's two beaver species, 393 00:24:50.480 --> 00:24:55.640 Castor canadensis, the North American beaver, and Castor fiber its 394 00:24:55.720 --> 00:24:59.519 Eurasian cousin, are vestiges of a diverse family. They are 395 00:24:59.519 --> 00:25:05.400 now extend Relatives include castory Days ohioensis, which grew nearly 396 00:25:05.440 --> 00:25:08.640 as large as black bears. Although it's tempting to imagine 397 00:25:08.680 --> 00:25:13.519 the custory Days constructing hoover dam side walls, these species 398 00:25:13.839 --> 00:25:17.559 likely didn't dam at all and died out during drier conditions. 399 00:25:17.960 --> 00:25:21.720 Modern beavers may have endured precisely because they could modify 400 00:25:21.799 --> 00:25:27.759 nature on a warming climate. As beavers proliferated, they shaped 401 00:25:27.799 --> 00:25:30.039