1 00:00:07,257 --> 00:00:09,843 Planet Earth is so spectacular, 2 00:00:10,636 --> 00:00:13,680 it's easy to miss the smaller things in life. 3 00:00:15,766 --> 00:00:17,643 But take a closer look... 4 00:00:18,143 --> 00:00:20,562 and there's a whole undiscovered world. 5 00:00:22,648 --> 00:00:24,983 A world where tiny heroes... 6 00:00:26,485 --> 00:00:27,861 and little monsters... 7 00:00:29,029 --> 00:00:31,406 need incredible superpowers... 8 00:00:34,618 --> 00:00:40,040 to help them triumph against giant odds. 9 00:00:57,391 --> 00:00:59,309 Life is full of hazards. 10 00:01:04,105 --> 00:01:08,110 Especially for a ground squirrel only the size of a taco. 11 00:01:14,491 --> 00:01:19,705 She makes her home in the cactus-covered land of America's Sonoran Desert. 12 00:01:23,834 --> 00:01:25,627 A tough place to make a living. 13 00:01:33,510 --> 00:01:37,514 Almost everything here is armed with claws... 14 00:01:38,849 --> 00:01:40,100 spines... 15 00:01:41,185 --> 00:01:42,603 or venom. 16 00:01:44,271 --> 00:01:46,064 Just surviving is hard enough. 17 00:01:47,608 --> 00:01:49,526 Let alone raising a family. 18 00:01:55,324 --> 00:01:56,867 When spring arrives, 19 00:01:56,950 --> 00:02:00,412 little desert creatures face their most challenging months. 20 00:02:10,172 --> 00:02:12,382 But if they stay ahead of their enemies... 21 00:02:15,302 --> 00:02:17,930 and play this prickly world to their advantage... 22 00:02:20,557 --> 00:02:24,394 being tiny might just give them the edge. 23 00:02:39,868 --> 00:02:41,161 Late spring. 24 00:02:44,831 --> 00:02:49,795 A ground squirrel pup seeing his desert home for the first time. 25 00:02:58,595 --> 00:03:02,266 For four weeks, he's been safe underground with mom... 26 00:03:10,399 --> 00:03:13,026 and his six brothers and sisters. 27 00:03:19,741 --> 00:03:25,163 But now he has a lot to learn about surviving in an unforgiving land. 28 00:03:30,043 --> 00:03:33,463 By the end of summer, this little pup will be on his own. 29 00:03:38,010 --> 00:03:41,972 Fortunately, his mom is an old hand at desert survival. 30 00:03:46,101 --> 00:03:49,438 Lesson number one: get to know the neighborhood. 31 00:03:53,317 --> 00:03:57,154 First impressions? Not all that welcoming. 32 00:04:00,324 --> 00:04:03,660 Huge saguaros tower 12 meters high. 33 00:04:05,120 --> 00:04:09,249 Just one of 300 species of cacti that grow here. 34 00:04:12,753 --> 00:04:14,755 Despite their menacing appearance, 35 00:04:15,422 --> 00:04:20,886 all sorts of animals rely on these prickly plants in all sorts of ways. 36 00:04:23,931 --> 00:04:25,015 An elf owl, 37 00:04:25,474 --> 00:04:30,562 the smallest owl in the world, nests high in the saguaro. 38 00:04:36,860 --> 00:04:40,948 Protected from the sun above and predators below. 39 00:04:42,866 --> 00:04:45,953 It's the perfect place to raise her new chicks. 40 00:04:51,667 --> 00:04:55,212 Down in the dust, other little creatures are up early... 41 00:05:00,676 --> 00:05:03,971 busy finding food before it gets too hot. 42 00:05:09,101 --> 00:05:10,352 They're a ravenous bunch. 43 00:05:20,028 --> 00:05:22,948 One of the residents here eats snakes for breakfast. 44 00:05:29,204 --> 00:05:30,205 The roadrunner... 45 00:05:33,667 --> 00:05:35,586 lives up to his name. 46 00:05:37,963 --> 00:05:40,591 He can run at 30 kilometers per hour. 47 00:05:49,641 --> 00:05:53,770 He needs to, to satisfy his family's growing hunger. 48 00:05:55,564 --> 00:06:01,028 Three chicks in a nest protected by a spiny security fence. 49 00:06:09,703 --> 00:06:12,497 Roadrunners will eat almost anything they can catch. 50 00:06:18,003 --> 00:06:20,339 But he won't bite off more than he can chew. 51 00:06:26,929 --> 00:06:30,349 A one-and-a-half-meter-long rattlesnake is too big. 52 00:06:33,227 --> 00:06:34,520 Too dangerous. 53 00:06:42,027 --> 00:06:44,738 While this venomous giant is in the neighborhood... 54 00:06:46,198 --> 00:06:49,159 little animals will have to watch their backs. 55 00:06:54,748 --> 00:06:57,376 Monsters patrol this desert too. 56 00:07:00,254 --> 00:07:01,380 Gila monsters. 57 00:07:05,175 --> 00:07:09,847 Nesting on open ground, rather than in cactus, is risky. 58 00:07:20,107 --> 00:07:24,111 Gambel's quails rely on camouflage to keep their eggs safe. 59 00:07:31,660 --> 00:07:33,537 But a Gila monster hunts by smell... 60 00:07:38,000 --> 00:07:39,877 sampling the air with its tongue. 61 00:07:50,179 --> 00:07:52,931 While there are such easy meals on the ground, 62 00:07:54,141 --> 00:07:57,519 the roadrunner chicks should be safe in their cactus nursery. 63 00:08:09,656 --> 00:08:13,160 A Gila monster is too big for a roadrunner to take on. 64 00:08:15,245 --> 00:08:17,748 Some lizards are more bite-sized... 65 00:08:20,417 --> 00:08:22,044 but harder to catch. 66 00:08:27,716 --> 00:08:30,344 A zebra-tail is one of the fastest. 67 00:08:33,138 --> 00:08:35,807 It also has a foolproof escape plan. 68 00:08:41,145 --> 00:08:44,358 A pile of dead cactus provides a safe bolt-hole... 69 00:08:45,859 --> 00:08:47,653 for lots of desert animals. 70 00:08:59,998 --> 00:09:01,917 And it's more than just a hideout. 71 00:09:05,128 --> 00:09:06,171 It's a home... 72 00:09:08,507 --> 00:09:10,092 for a little pack rat. 73 00:09:18,600 --> 00:09:20,811 She's the architect of this fortress. 74 00:09:22,479 --> 00:09:25,190 An expert in construction with cacti. 75 00:09:30,362 --> 00:09:33,282 Any gap in her defenses is easily patched. 76 00:09:38,453 --> 00:09:41,665 These barbed wire balls are in plentiful supply. 77 00:09:46,587 --> 00:09:52,342 A well-maintained pack rat den makes life very difficult for predators. 78 00:10:11,236 --> 00:10:13,906 There are so many impenetrable hiding places 79 00:10:14,489 --> 00:10:17,492 and fortified homes in the cactus desert, 80 00:10:18,744 --> 00:10:22,080 a lone Harris's hawk struggles to catch enough prey. 81 00:10:26,335 --> 00:10:29,421 But this hunter has a deadly backup plan. 82 00:10:33,926 --> 00:10:37,721 The young ground squirrel must learn never to stray far from cover. 83 00:10:41,808 --> 00:10:44,520 But mom has another vital lesson to teach him. 84 00:10:49,149 --> 00:10:52,152 Three quarters of a cactus's weight is water. 85 00:10:56,490 --> 00:11:01,537 They serve as reliable reservoirs even when rain is months away. 86 00:11:12,089 --> 00:11:13,632 Pups catch on fast. 87 00:11:15,342 --> 00:11:17,678 But don't always pay attention. 88 00:11:25,644 --> 00:11:29,106 Diamondback rattlesnakes are ambush predators 89 00:11:29,940 --> 00:11:32,568 with enough venom to kill a human. 90 00:11:34,570 --> 00:11:36,238 Mom is always on high alert. 91 00:11:39,950 --> 00:11:42,244 But she needs to make sure her pups are too. 92 00:11:47,124 --> 00:11:53,213 And show them how to face down an enemy ten times her size. 93 00:12:01,889 --> 00:12:05,017 Flagging her tail makes her pups aware of the danger... 94 00:12:07,186 --> 00:12:12,065 and lets the snake know its surprise attack has been foiled. 95 00:12:18,447 --> 00:12:20,032 A bold move... 96 00:12:21,992 --> 00:12:23,202 but it works. 97 00:12:28,749 --> 00:12:31,919 With more rattlesnakes here than anywhere else on earth, 98 00:12:32,002 --> 00:12:35,797 this is one lesson the little pup cannot forget. 99 00:12:41,970 --> 00:12:46,767 By early summer, temperatures are hitting 40 degrees Celsius. 100 00:12:57,402 --> 00:12:59,738 Nightfall brings relief from the heat... 101 00:13:01,156 --> 00:13:04,660 and new hunting opportunities. 102 00:13:08,956 --> 00:13:13,794 The elf owl chicks are growing bigger and hungrier. 103 00:13:27,599 --> 00:13:30,894 It's now cool enough for the pack rat to leave her fortress 104 00:13:31,603 --> 00:13:33,146 and find food. 105 00:13:38,277 --> 00:13:41,196 Seventy percent of her diet is cactus, 106 00:13:41,822 --> 00:13:43,907 so she doesn't have to look too far. 107 00:13:48,912 --> 00:13:53,625 At night, the desert crawls with all sorts of little killers. 108 00:14:14,313 --> 00:14:19,276 But the most sinister looking are by no means the most deadly. 109 00:14:32,664 --> 00:14:36,210 In three weeks, the owlets have quadrupled in size... 110 00:14:40,005 --> 00:14:42,257 and have insatiable appetites. 111 00:14:47,095 --> 00:14:51,558 Their doting parents will make 80 kills a night to keep them fed. 112 00:15:13,080 --> 00:15:16,083 Until their chicks fledge in two weeks' time, 113 00:15:16,708 --> 00:15:18,710 the feeding frenzy continues... 114 00:15:19,920 --> 00:15:22,256 night after night. 115 00:15:34,393 --> 00:15:35,811 As summer draws on, 116 00:15:35,894 --> 00:15:39,940 the cacti present another gift for little desert animals. 117 00:15:43,569 --> 00:15:47,447 Nocturnal blooms, brimming with nectar. 118 00:15:55,038 --> 00:15:58,792 Lesser long-nosed bats are only the weight of a teaspoon, 119 00:15:58,876 --> 00:16:02,379 but they fly hundreds of miles to reach this feast. 120 00:16:07,968 --> 00:16:11,513 These flowers offer more nectar than almost any other. 121 00:16:14,516 --> 00:16:18,812 And as the bats visit more blooms, they pollinate them along the way. 122 00:16:30,073 --> 00:16:34,745 But when each flower opens, the cactus loses precious water. 123 00:16:38,832 --> 00:16:40,751 So they only open once. 124 00:16:42,920 --> 00:16:44,296 And for less than a day. 125 00:17:06,151 --> 00:17:09,320 As different cacti bloom through spring and summer, 126 00:17:09,404 --> 00:17:12,241 they provide a much-needed food source. 127 00:17:21,083 --> 00:17:22,751 With mom's guidance, 128 00:17:22,835 --> 00:17:26,839 the eight-week-old pup is learning when and where to find them. 129 00:17:36,139 --> 00:17:38,016 Even the petals are nutritious. 130 00:17:41,103 --> 00:17:44,606 Packed with the protein and carbs a growing pup needs. 131 00:17:51,321 --> 00:17:53,115 These flowers may be fleeting... 132 00:17:55,617 --> 00:18:01,206 but some tiny creatures have an ingenious way of preserving their riches. 133 00:18:11,091 --> 00:18:13,385 Hidden deep underground... 134 00:18:14,678 --> 00:18:19,099 a nest stocked with a treasured liquid. 135 00:18:31,528 --> 00:18:35,282 Honeypot ants are stuffed with so much nectar, 136 00:18:35,908 --> 00:18:37,993 they swell as large as a grape. 137 00:18:40,787 --> 00:18:43,040 Twenty times their original size. 138 00:18:56,220 --> 00:18:59,348 These living storage containers can hardly move... 139 00:19:00,682 --> 00:19:03,227 and have to be cared for by the other ants. 140 00:19:15,405 --> 00:19:17,366 When the outside world is barren, 141 00:19:18,033 --> 00:19:21,370 this liquid gold sustains the whole colony 142 00:19:22,162 --> 00:19:23,956 until better times return. 143 00:19:38,428 --> 00:19:42,850 By midsummer, the temperature reaches 50 degrees Celsius. 144 00:19:48,981 --> 00:19:51,108 Everyone's baking in the heat. 145 00:19:53,277 --> 00:19:55,779 And the young are the most vulnerable. 146 00:19:58,240 --> 00:20:01,702 Dad takes the full force of the sun to shade his chicks. 147 00:20:12,004 --> 00:20:14,840 But the elf owl family can sleep comfortably. 148 00:20:17,384 --> 00:20:21,638 Water evaporating from the saguaro's trunk cools the interior 149 00:20:22,598 --> 00:20:24,808 and keeps their nest air-conditioned. 150 00:20:32,858 --> 00:20:36,945 A thick cactus roof keeps the pack rat's home cool too. 151 00:20:40,157 --> 00:20:43,410 Essential, now that it's become a nursery. 152 00:20:48,165 --> 00:20:52,920 Four peanut-sized pups, blind and helpless. 153 00:20:54,421 --> 00:20:56,298 They need their mother's protection. 154 00:21:03,347 --> 00:21:07,935 In this heat, even cold-blooded killers seek shade. 155 00:21:12,356 --> 00:21:17,194 And the pack rat's nest becomes a refuge for unwelcome guests. 156 00:21:25,786 --> 00:21:30,832 Passed down from mother to daughter, these dens can be centuries old. 157 00:21:36,338 --> 00:21:39,466 And extensive enough to keep nasty neighbors apart. 158 00:21:47,975 --> 00:21:51,311 And anyway, it's way too hot to hunt. 159 00:22:00,070 --> 00:22:04,908 In a summer this severe, the cacti shrink to two thirds their diameter. 160 00:22:14,376 --> 00:22:19,840 As temperatures peak, finally change is in the air. 161 00:22:24,761 --> 00:22:27,306 But this storm brings no relief. 162 00:22:31,852 --> 00:22:34,938 A 100-kilometer wall of dust. 163 00:22:58,879 --> 00:23:03,342 In its wake, a sign of more trouble ahead. 164 00:23:10,641 --> 00:23:15,354 Each time a rattlesnake sheds its skin, it's only getting bigger. 165 00:23:25,364 --> 00:23:28,200 At least the pup has learned to be more wary. 166 00:23:36,792 --> 00:23:38,168 But this is not a threat. 167 00:23:40,003 --> 00:23:43,882 It's an opportunity for mom to teach him another survival secret. 168 00:23:49,012 --> 00:23:50,764 Chewing the skin into a paste... 169 00:23:53,725 --> 00:23:55,477 and rubbing it into her fur, 170 00:23:56,395 --> 00:24:00,983 makes her smell less like a squirrel and more like a snake. 171 00:24:08,156 --> 00:24:13,287 As long as he keeps copying mom, the pup should be safe. 172 00:24:25,465 --> 00:24:27,843 But the roadrunner's chicks will fledge soon... 173 00:24:28,927 --> 00:24:33,223 and away from the nest, they'll be more exposed. 174 00:24:44,276 --> 00:24:48,363 Their father must do all he can to keep their patch of desert safe. 175 00:24:55,954 --> 00:25:00,292 Like a matador, he provokes his enemy. 176 00:25:06,381 --> 00:25:08,926 Goading it to attack his wing feathers... 177 00:25:10,719 --> 00:25:12,262 where it can do no harm. 178 00:25:33,075 --> 00:25:36,370 Until finally, it's had enough. 179 00:25:39,289 --> 00:25:41,124 Hopefully, it won't be back 180 00:25:41,208 --> 00:25:44,878 before the roadrunner chicks can fend for themselves. 181 00:25:53,345 --> 00:25:58,725 Just after summer peaks, relief finally arrives. 182 00:26:14,700 --> 00:26:19,580 Monsoon storms drop ten centimeters of rain in just a few hours. 183 00:26:31,383 --> 00:26:35,637 It only takes one downpour to revitalize the land. 184 00:26:41,059 --> 00:26:45,689 The cacti swell, replenishing their water stores. 185 00:26:48,525 --> 00:26:53,030 Enough to see this patch of desert through many months to come. 186 00:27:00,704 --> 00:27:03,957 The ground squirrel pup is almost ready to go it alone. 187 00:27:11,757 --> 00:27:14,510 But the Harris's hawk is back. 188 00:27:30,067 --> 00:27:33,195 And this time, with reinforcements. 189 00:27:36,281 --> 00:27:39,743 The cactus desert offers little creatures so much cover, 190 00:27:41,411 --> 00:27:44,623 it forces Harris's hawks to hunt in packs. 191 00:27:55,467 --> 00:27:59,054 Working together to flush out their victims. 192 00:28:03,976 --> 00:28:07,980 These long-legged raptors are just as deadly on the ground. 193 00:28:44,349 --> 00:28:46,560 Mom can only hope her pup stays put... 194 00:28:51,982 --> 00:28:53,192 and doesn't panic. 195 00:29:15,756 --> 00:29:16,840 He's made it. 196 00:29:21,803 --> 00:29:26,433 Under his mother's guidance, he now has all the skills he needs 197 00:29:26,517 --> 00:29:30,103 to turn a prickly problem into an advantage. 198 00:29:35,692 --> 00:29:37,361 They may look intimidating, 199 00:29:37,945 --> 00:29:41,657 but these cacti provide everything a little creature needs... 200 00:29:44,326 --> 00:29:47,955 to call this place home.