WEBVTT - Can Different Species of Birds Understand Each Other? 0:00:02.040 --> 0:00:07.040 Welcome to brain Stuff from how stuff works, Hey, brain Stuff, 0:00:07.080 --> 0:00:10.400 Lauren Vogel bomb Here. A good birdwatcher can identify the 0:00:10.440 --> 0:00:13.640 local species not just by sight, but also by sound. 0:00:14.120 --> 0:00:17.760 It's something the Audubon Society calls birding by ear. With 0:00:17.800 --> 0:00:21.040 practice and a good field guide, avian enthusiasts learned to 0:00:21.120 --> 0:00:25.120 recognize the trademark tweets, cheeps, and hoots that various birds omit. 0:00:26.040 --> 0:00:29.200 Mastering this skill requires a basic understanding of how and 0:00:29.240 --> 0:00:33.160 why are feathered friends communicate. Often, a given species will 0:00:33.240 --> 0:00:36.160 use its own distinctive set of sounds, like mating calls 0:00:36.200 --> 0:00:40.000 and territorial threats to get assorted points across. Take the 0:00:40.080 --> 0:00:49.440 rock pigeon. These guys cord each other with gentle coups 0:00:49.920 --> 0:01:01.320 and too signal distress. They use a harsh grunt. If 0:01:01.320 --> 0:01:04.360 an individual rock pigeon is to survive and procreate, it 0:01:04.440 --> 0:01:08.160 must be able to recognize both vocalizations. But do what 0:01:08.240 --> 0:01:12.240 pigeons noises mean anything to passing crows or cardinals? Can 0:01:12.280 --> 0:01:16.560 birds understand the calls made by other species? We recently 0:01:16.600 --> 0:01:19.640 discussed this topic with Robert de McGrath, an ornithologist and 0:01:19.680 --> 0:01:23.800 behavioral ecologist at the Australian National University. McGrath has co 0:01:23.880 --> 0:01:28.120 authored multiple studies about interspecies communication in birds. Much of 0:01:28.160 --> 0:01:30.920 his research has dealt with avian alarm calls. These are 0:01:30.959 --> 0:01:33.440 the warning cries that birds send out when a predator 0:01:33.520 --> 0:01:37.200 is cited. As McGrath tells us via email, just about 0:01:37.200 --> 0:01:40.120 every bird species we have studied locally respond to other 0:01:40.160 --> 0:01:43.680 species alarm calls, and we suspect eavesdropping on other species 0:01:43.720 --> 0:01:47.560 calls is widespread around the globe. Perhaps this is not surprising, 0:01:47.560 --> 0:01:50.720 given that almost all species are vulnerable to predators and 0:01:50.720 --> 0:01:53.720 so should use any available cues that predators are around. 0:01:54.680 --> 0:01:56.880 One good example of this phenomenon can be found in 0:01:56.920 --> 0:02:00.840 the relationship between black capped chicken eas and redbreast a nuthatches. 0:02:01.320 --> 0:02:04.160 The two songbirds have much in common. Both species are 0:02:04.200 --> 0:02:07.840 indigenous to North America and attain similar sizes. They're also 0:02:07.880 --> 0:02:11.120 a wary of raptors. When chicken ees see a gosshawk 0:02:11.160 --> 0:02:14.120 owl or some other winged predator, the birds issue an 0:02:14.120 --> 0:02:24.359 alarm call. Like the t s A, their warnings recognize 0:02:24.400 --> 0:02:28.000 different threat levels. High pitched seat calls are used to 0:02:28.120 --> 0:02:31.320 tip off other birds about a raptor that's flying far overhead. 0:02:31.800 --> 0:02:34.920 The eponymous chickend e d cry rings out whenever a 0:02:35.000 --> 0:02:38.600 perched raptor is seen nearby. Extra d s are added 0:02:38.639 --> 0:02:42.359 if a killer looks especially dangerous. Research has shown that 0:02:42.400 --> 0:02:46.440 other birds, like red breasted nuthatches, understand the chicken eese warnings, 0:02:46.760 --> 0:02:49.840 and with close listening, they can decode the exact degree 0:02:49.840 --> 0:02:53.480 of danger that's being advertised in these alarm calls. Clearly, 0:02:53.600 --> 0:02:57.239 eavesdropping has its benefits. Alarm calls can even trigger a 0:02:57.320 --> 0:03:01.240 response from non avian listeners. The tough to tipmouse, for example, 0:03:01.360 --> 0:03:04.320 is a songbird whose anti raptor warning cries send squirrels 0:03:04.320 --> 0:03:14.800 and chipmunks running amazingly. These mammals are known to spread 0:03:14.880 --> 0:03:19.440 the distress signal by imitating it with their own voices. Sparrows, cardinals, 0:03:19.440 --> 0:03:23.360 and jays will also mimic the tipmouse's signature alarm call. Thus, 0:03:23.360 --> 0:03:28.520 an interspecies chorus heralds the arrival of an oncoming threat. Okay, 0:03:28.800 --> 0:03:31.639 so do birds just have an innate understanding of other 0:03:31.639 --> 0:03:34.320 species alarm calls or do they pick up the skill 0:03:34.400 --> 0:03:37.880 over time? McGraph says that at least in some cases, 0:03:38.000 --> 0:03:42.000 certain birds actively learn to identify the cries, superb very 0:03:42.040 --> 0:03:44.840 wrens are a common sight on the Australian National University 0:03:44.880 --> 0:03:56.680 campus in Canberra. As it happens, the school grounds also 0:03:56.720 --> 0:03:59.160 received plenty of visits from a gray bird known as 0:03:59.160 --> 0:04:11.400 the noisy inner. According to McGrath, there's a botanical garden 0:04:11.440 --> 0:04:13.640 across the street where the wrens like to hang out, 0:04:13.960 --> 0:04:16.440 but the miners avoid it. In one of his studies, 0:04:16.440 --> 0:04:19.000 he was able to demonstrate that superb fairy wrens who 0:04:19.040 --> 0:04:22.159 lived on campus fled when a recording of minor alarm 0:04:22.240 --> 0:04:25.600 calls was played. However, the wrens at the botanical garden, 0:04:25.720 --> 0:04:28.680 where again no miners are present, did not react to 0:04:28.720 --> 0:04:33.240 the same recording. This strongly suggests that interspecies call recognition 0:04:33.320 --> 0:04:36.480 is an't innate, it has to be learned. McGrath notes 0:04:36.800 --> 0:04:40.679 we've subsequently even trained fairy wrens to recognize novel sounds 0:04:40.720 --> 0:04:43.200 as alarm calls by pairing them with the presentation of 0:04:43.240 --> 0:04:48.159 gliding hawk models, which unequivocally shows learning Alarm calls aren't 0:04:48.200 --> 0:04:51.599 the only vocalizations that can transcend species. It's common for 0:04:51.640 --> 0:04:54.560 birds to recognize other birds species sounds if there's some 0:04:54.600 --> 0:04:59.320 benefit to recognition. McGrath said. Some species defend territories against 0:04:59.360 --> 0:05:02.600 members of others species and respond to their territorial song. 0:05:03.080 --> 0:05:06.239 Others can recognize contact calls, which helps them form mixed 0:05:06.279 --> 0:05:10.200 species flocks and find food. And then there's the cuckoo 0:05:10.279 --> 0:05:13.760 and notorious brewed parasite. Females lay their eggs in the 0:05:13.800 --> 0:05:16.560 nests of other birds, who are then sometimes tricked into 0:05:16.640 --> 0:05:19.839 raising the cuckoo's chicks to pull off the charade. Baby 0:05:19.880 --> 0:05:22.880 cuckoos imitate the begging cries made by infants of the 0:05:22.880 --> 0:05:26.760 host's own species, but these sorts of imitable cries aren't 0:05:26.800 --> 0:05:29.640 made by single species alone, like chicken ee. The name 0:05:29.680 --> 0:05:32.680 cucka Bara is on Amano Peak. It's derived from the 0:05:32.720 --> 0:05:44.160 world famous cackle made by these birds. Hollywood seems obsessed 0:05:44.160 --> 0:05:47.279 with their exotic laugh. Cucka Bara cries can be heard 0:05:47.279 --> 0:05:49.960 in the background of such films as Raiders Have Lost Arc, 0:05:50.120 --> 0:05:58.520 The Naked Gun, and assorted Tarzan movies. Today's episode was 0:05:58.520 --> 0:06:01.560 written by Mark Mancini and preduced by Tyler Clang. For 0:06:01.640 --> 0:06:04.240 more on this and lots of other barrier busting topics, 0:06:04.400 --> 0:06:18.280 visit our home planet how Stuff Works dot com.