[Script Info]
Title: 
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:00.56,0:00:03.06,Default,,0000,0000,0000,,(comical synthesized music)
Dialogue: 0,0:00:03.06,0:00:06.48,Default,,0000,0000,0000,,NARRATOR: They're extremely awkward on land...
Dialogue: 0,0:00:09.10,0:00:11.37,Default,,0000,0000,0000,,And not exactly graceful in the water.
Dialogue: 0,0:00:13.14,0:00:16.85,Default,,0000,0000,0000,,But there's something endearing about these egg-laying mammals.
Dialogue: 0,0:00:17.42,0:00:20.62,Default,,0000,0000,0000,,Platypuses can only be found in the rivers, streams, and lakes
Dialogue: 0,0:00:20.62,0:00:23.68,Default,,0000,0000,0000,,along the East Coast of Australia.
Dialogue: 0,0:00:25.09,0:00:28.73,Default,,0000,0000,0000,,But they range as far North as Northern Queensland, all the way down
Dialogue: 0,0:00:28.73,0:00:31.19,Default,,0000,0000,0000,,to the Southern island of Tasmania.
Dialogue: 0,0:00:32.09,0:00:34.60,Default,,0000,0000,0000,,That's quite a range for these little creatures.
Dialogue: 0,0:00:34.60,0:00:36.94,Default,,0000,0000,0000,,But there are gaps between populations.
Dialogue: 0,0:00:36.94,0:00:39.80,Default,,0000,0000,0000,,Large tracts of land between the rivers and lakes
Dialogue: 0,0:00:39.80,0:00:44.28,Default,,0000,0000,0000,,make it difficult for the platypuses to migrate from one area to another.
Dialogue: 0,0:00:45.51,0:00:47.18,Default,,0000,0000,0000,,Researchers believe it's possible
Dialogue: 0,0:00:47.18,0:00:50.85,Default,,0000,0000,0000,,that isolated pockets of animals could have evolved differently,
Dialogue: 0,0:00:50.85,0:00:53.71,Default,,0000,0000,0000,,could even be separate subspecies.
Dialogue: 0,0:00:54.56,0:00:59.12,Default,,0000,0000,0000,,The interesting things about platypus are that, as you come up the coast from Tasmania,
Dialogue: 0,0:00:59.12,0:01:01.53,Default,,0000,0000,0000,,they get smaller.
Dialogue: 0,0:01:01.53,0:01:05.100,Default,,0000,0000,0000,,As well as that, their body size is actually less in some of the Northern ones,
Dialogue: 0,0:01:05.100,0:01:08.36,Default,,0000,0000,0000,,so the maximum weight for one in this area
Dialogue: 0,0:01:08.36,0:01:12.96,Default,,0000,0000,0000,,is somewhere in the region of a kilogram, about two and a half pounds.
Dialogue: 0,0:01:12.96,0:01:17.44,Default,,0000,0000,0000,,Whereas they're around about three times that weight in Tasmania.
Dialogue: 0,0:01:17.44,0:01:20.61,Default,,0000,0000,0000,,NARRATOR: Stephen Kolomyjec from James Cook University
Dialogue: 0,0:01:20.61,0:01:25.96,Default,,0000,0000,0000,,is using genetic material to determine gene flow from one population to another.
Dialogue: 0,0:01:25.96,0:01:27.82,Default,,0000,0000,0000,,He examines the size and health
Dialogue: 0,0:01:27.82,0:01:30.42,Default,,0000,0000,0000,,of populations as well.
Dialogue: 0,0:01:30.42,0:01:36.23,Default,,0000,0000,0000,,What fascinates him the most are the differences between the Northern and Southern platypuses.
Dialogue: 0,0:01:36.23,0:01:39.67,Default,,0000,0000,0000,,The platypuses up here in North Queensland are about a third of the size of the ones down South,
Dialogue: 0,0:01:39.67,0:01:42.49,Default,,0000,0000,0000,,which is a pretty big size difference.
Dialogue: 0,0:01:42.49,0:01:45.60,Default,,0000,0000,0000,,It may be because of climate, but it may be because of actual differences
Dialogue: 0,0:01:45.60,0:01:47.71,Default,,0000,0000,0000,,in the species itself.
Dialogue: 0,0:01:47.71,0:01:51.13,Default,,0000,0000,0000,,BLAIR: Populations here are isolated from the populations in the South,
Dialogue: 0,0:01:51.13,0:01:54.75,Default,,0000,0000,0000,,so we're interested in looking at the effects of the gaps in the range,
Dialogue: 0,0:01:54.75,0:01:59.12,Default,,0000,0000,0000,,and especially this far North, and one of the tools that we're using to do that
Dialogue: 0,0:01:59.12,0:02:01.98,Default,,0000,0000,0000,,is population genetics.
Dialogue: 0,0:02:05.67,0:02:09.03,Default,,0000,0000,0000,,NARRATOR: Stephen and his colleague David Blair are working in some of the oldest
Dialogue: 0,0:02:09.03,0:02:11.80,Default,,0000,0000,0000,,rainforest in the world.
Dialogue: 0,0:02:11.80,0:02:13.10,Default,,0000,0000,0000,,KOLOMYJEC: This is Dirran Creek.
Dialogue: 0,0:02:13.10,0:02:17.34,Default,,0000,0000,0000,,It's a tributary of the North Johnstone River Catchment.
Dialogue: 0,0:02:17.34,0:02:21.48,Default,,0000,0000,0000,,It's one of the many Upland freshwater streams in North Queensland,
Dialogue: 0,0:02:21.48,0:02:24.31,Default,,0000,0000,0000,,and it's abundant in platypuses.
Dialogue: 0,0:02:24.31,0:02:28.47,Default,,0000,0000,0000,,NARRATOR: Collecting genetic samples from a platypus can be rather challenging.
Dialogue: 0,0:02:28.47,0:02:31.62,Default,,0000,0000,0000,,Special nets are carefully placed in the streams.
Dialogue: 0,0:02:31.62,0:02:35.43,Default,,0000,0000,0000,,They're not weighted down, so platypuses can swim up to the surface
Dialogue: 0,0:02:35.43,0:02:39.38,Default,,0000,0000,0000,,once they become entangled, to prevent drowning.
Dialogue: 0,0:02:39.38,0:02:43.30,Default,,0000,0000,0000,,With the nets in place, the team awaits until nightfall, when platypuses
Dialogue: 0,0:02:43.30,0:02:45.60,Default,,0000,0000,0000,,are more active.
Dialogue: 0,0:02:45.60,0:02:48.53,Default,,0000,0000,0000,,Then it's time to collect their subjects.
Dialogue: 0,0:02:49.57,0:02:56.54,Default,,0000,0000,0000,,Here's something most people might not be aware of: A platypus should always be held by its tail.
Dialogue: 0,0:02:56.54,0:02:58.93,Default,,0000,0000,0000,,Especially if it's a male.
Dialogue: 0,0:02:58.93,0:03:03.72,Default,,0000,0000,0000,,They're one of the few venomous mammals, with a spur on the hind foot
Dialogue: 0,0:03:03.72,0:03:06.32,Default,,0000,0000,0000,,capable of injecting some rather potent
Dialogue: 0,0:03:06.32,0:03:08.59,Default,,0000,0000,0000,,and painful venom.
Dialogue: 0,0:03:08.59,0:03:14.12,Default,,0000,0000,0000,,So gripping the fatty tail is best for the platypus and the handler.
Dialogue: 0,0:03:14.12,0:03:17.23,Default,,0000,0000,0000,,Now it's time to collect the necessary data.
Dialogue: 0,0:03:17.23,0:03:18.100,Default,,0000,0000,0000,,The platypus is weighed...
Dialogue: 0,0:03:18.100,0:03:19.60,Default,,0000,0000,0000,,KOLOMYJEC: 200.
Dialogue: 0,0:03:19.60,0:03:21.50,Default,,0000,0000,0000,,NARRATOR: And measured, both the body...
Dialogue: 0,0:03:21.50,0:03:22.25,Default,,0000,0000,0000,,KOLOMYJEC: 43.
Dialogue: 0,0:03:22.25,0:03:23.87,Default,,0000,0000,0000,,NARRATOR: And the sizable bill.
Dialogue: 0,0:03:23.87,0:03:25.03,Default,,0000,0000,0000,,KOLOMYJEC: 53.
Dialogue: 0,0:03:25.03,0:03:28.79,Default,,0000,0000,0000,,NARRATOR: The scientists extract samples of DNA.
Dialogue: 0,0:03:28.79,0:03:31.90,Default,,0000,0000,0000,,BLAIR: The principal samples that we're collecting for that is a small piece of skin
Dialogue: 0,0:03:31.90,0:03:35.42,Default,,0000,0000,0000,,from the toe web on the edge of the foot.
Dialogue: 0,0:03:35.42,0:03:39.49,Default,,0000,0000,0000,,That gives us enough DNA, when we take that back to the laboratory,
Dialogue: 0,0:03:39.49,0:03:42.82,Default,,0000,0000,0000,,to be able to do quite a lot of genetic analysis.
Dialogue: 0,0:03:42.82,0:03:47.93,Default,,0000,0000,0000,,In addition to that, we're collecting a little bit of toe skin to go to a laboratory in Adelaide,
Dialogue: 0,0:03:47.93,0:03:52.87,Default,,0000,0000,0000,,where researchers are making cell cultures, for further genetic work.
Dialogue: 0,0:03:52.87,0:03:54.60,Default,,0000,0000,0000,,They're interested in chromosome studies.
Dialogue: 0,0:03:54.60,0:04:00.14,Default,,0000,0000,0000,,They're interested in studies on the rather strange sex chromosomes that platypus have.
Dialogue: 0,0:04:00.14,0:04:05.38,Default,,0000,0000,0000,,Well, most mammals have an XY sex-determining system.
Dialogue: 0,0:04:05.38,0:04:09.57,Default,,0000,0000,0000,,Well, the platypus has gone rather a long way further than that.
Dialogue: 0,0:04:09.57,0:04:13.75,Default,,0000,0000,0000,,The platypus has five X chromosomes and five Y chromosomes.
Dialogue: 0,0:04:13.75,0:04:16.19,Default,,0000,0000,0000,,You can ask the question "Why?"
Dialogue: 0,0:04:16.19,0:04:18.39,Default,,0000,0000,0000,,I can't give you an answer.
Dialogue: 0,0:04:18.39,0:04:20.46,Default,,0000,0000,0000,,NARRATOR: Once the platypus is microchipped...
Dialogue: 0,0:04:20.46,0:04:21.09,Default,,0000,0000,0000,,KOLOMYJEC: There we go.
Dialogue: 0,0:04:21.09,0:04:24.20,Default,,0000,0000,0000,,NARRATOR: It's released back into the water.
Dialogue: 0,0:04:24.20,0:04:26.23,Default,,0000,0000,0000,,KOLOMYJEC: Just let him go gently.
Dialogue: 0,0:04:26.23,0:04:29.12,Default,,0000,0000,0000,,We hope to learn how much difference there is between Northern populations
Dialogue: 0,0:04:29.12,0:04:30.84,Default,,0000,0000,0000,,from Southern populations.
Dialogue: 0,0:04:30.84,0:04:33.74,Default,,0000,0000,0000,,Up here in the North, there are a few gaps where they just do not occur.
Dialogue: 0,0:04:33.74,0:04:36.51,Default,,0000,0000,0000,,And there are no historical records of them ever occurring in those areas.
Dialogue: 0,0:04:36.51,0:04:41.45,Default,,0000,0000,0000,,And so we're looking at what kind of effect these gaps have had on their genetic health.
Dialogue: 0,0:04:41.45,0:04:44.82,Default,,0000,0000,0000,,The actual species -- they might be very different, they might not be different.
Dialogue: 0,0:04:44.82,0:04:50.40,Default,,0000,0000,0000,,It depends on when the last platypus was able to cross these gaps.
Dialogue: 0,0:04:51.49,0:04:54.46,Default,,0000,0000,0000,,NARRATOR: If the smaller Northern platypuses are found to be genetically different
Dialogue: 0,0:04:54.46,0:05:00.20,Default,,0000,0000,0000,,from the Southern platypuses, they may be recognized as a newly identified subspecies,
Dialogue: 0,0:05:00.20,0:05:07.44,Default,,0000,0000,0000,,making them an even more unique version of one of the most unique animals on the planet.
Dialogue: 0,0:05:11.38,0:05:14.31,Default,,0000,0000,0000,,ANNOUNCER: Sponsored by National Geographic Mission Programs,
Dialogue: 0,0:05:14.31,0:05:17.05,Default,,0000,0000,0000,,taking science and exploration
Dialogue: 0,0:05:17.05,9:59:59.99,Default,,0000,0000,0000,,into the new millennium.