A STUDYGUIDE BY ANDREW FILDES 11 www.metromagazine.com.au www.theeducationshop.com.au Overview Planet Earth is a BBC production with five episodes in the first series (episodes one through five) and six episodes in the second series (episodes six through eleven). Each episode examines a specific environment, focussing on key species or relationships in each habitat; the challenges they face; the behaviours they exhibit and the adaptations that enable them to survive. Recent advances in photography are used to achieve some spectacular ‘first sights’ – in particular, stabilised aerial photography gives us remarkable views of migrating animals and the techniques used by their predators to hunt them. As the series examines pristine environments where possible, they are often extreme. These are the parts of the world where few humans have chosen to live as the climate and landscape is too challenging, too difficult and dangerous. The plants and animals that do survive here have made some spectacular adaptations in forms and behaviour to live in these far reaches of the planet. The series is suitable for middle secondary students studying Science and SOSE, and for senior secondary students of Biology, Environmental Science and Geography. SCREEN EDUCATION 2 1 Episode Eleven: Ocean and crustaceans that huddle around gered more by the threats to its food Deep volcanic fissures on the ocean floor, source than hunting, as in the past. outpourings of superheated water in so The deep oceans, the pelagic zone cov- called ‘black smokers’. The plumes of Resources ers more than half our planet’s surface mineral rich hot water form huge chim- and is one of the least explored areas. neys and whole, unique ecosystems http://www.pbs.org/saf/1207/ Much of it is simply an empty blackness tread a fine line between that water features/113.htm (Black Smoker but the upper reaches are a vital part of venting at hundreds of degrees and the Discovery) the earth’s habitat and climatic systems freezing deeps around them. These are 3D IMAX movie – Aliens of the Deep and even the deepest, darkest zones contrasted with the great seamounts, hold some remarkable surprises. undersea volcanoes that rise kilometres Species List from the abyss to provide a platform for We begin with the largest fish of all, the life. Some like Ascension Island in the Whale Shark – Rhinocodon typus harmless whale shark that was almost Atlantic break the surface and create Yellowfin Tuna – Thunnus albacares unknown a few years ago but has now a special habitat for frigate birds and Oceanic White Tip Shark – Carcharhi- become a tourist spectacle in many turtles. Finally we return to the ocean gi- nus longimanus places. It cruises the warm waters of ants, creatures that could only live here Pilot Fish – Naucrates ductor the sub-tropical reefs, swallowing huge with the limitless space and the support Rainbow Runners – Elagatis bipin- quantities of plankton and small fish, as of the water. But this time it is the great nulata does the manta ray, master of underwa- blue whale, the largest animal ever to Dolphin – Tursiops spp., Delphinus ter flight. These are the great grazers of have lived on earth and now endan- spp. the ocean, scooping up the microscop- Blue Jack Mackerel – Trachurus pic- ic plants and some small animals too. turatus True predators like the white tip shark Episode 11: Ocean Deep Time Log Cory’s Shearwater – Calonectris di- are long distance hunters, cruising the omedea borealis vast reaches of the open ocean in the Intro 00:00 - 01:25 Mobula Ray – Mobula spp. constant hunt for scarce food while Whale Shark 01:25 - 05:00 Indo-Pacific Sailfish – istiophorus large tribes of dolphins take a more platypterus proactive approach, herding their prey White Tip Shark 05:00 - 07:20 Manta Ray – Manta birostris into tight bunches before they strike Pteropod (Sea Butterfly) – Theco- Dolphin and Shearwater 07:20 - 11:10 mercilessly. somata Plankton Night Grazers 11:10 - 13:53 Sea Cucumber – Holothuroidea But beneath the warm and sunlit waters Sea Spider – Muneurycope spp. of the surface lie unimaginable depths Submarine Descent 13;53 - 17:30 Sawtooth Eel – Serrivomer spp. of dark, cold water. Some animals may Vampire Squid 17:30 - 18:57 Dumbo Octopus – Grimpoteuthis spp. dive down there hunting food but most Vampire Squid – Vampyroteuthis of it is a high pressure desert, inhabited Deep Ocean Floor 18:57 - 23:55 infernalis by strange beasts that live on what- Atlantic Smokers 23:55 - 25:26 Sea Urchin – Phormosoma placenta ever falls, dead, from the upper levels. Monkfish – Lophius piscatorious These are highly specialized creatures, Dragon Chimneys 25:26 - 27:03 Giant Isopod – Bathynomus giganteus adapted to filter their food blindly from Death of a Vent 27:03 - 28:56 Sperm Whale – Physeter macrocepha- the downward drifting ‘snow’ or to hunt lus each other in the total dark above the Sea Mounts 28:56 - 31:10 Spider Crabs – Hyas spp. great plains of sand and ooze. Like Squat Lobster – Shinkaia crosnieri Nautilus 31:10 - 33:24 the vampire squid which can light up Giant Tubeworm – Riftia pachyptila to confuse its predators or prey and Dolphin and Squid 33:24 - 36:00 Whip Corals – Iridgorgia spp. the scavengers of the plains sifting out Chambered Nautilus – Nautilus pom- Sunfish 36:00 - 37:00 any organic particles from the ocean pilius floor. Eventually even the giants die and Frigate Birds on Ascen- 37:00 - 41:56 Pacific Spotted dolphin – Stenella SCREEN EDUCATION the carcass of a huge sperm whale is sion attenuata slowly consumed by the scavengers of Ocean Sunfish – Mola mola Green Turtle Hatching 38:50 - 41:32 the abyss. Ascension Frigate Bird – Fregata Sailfish 41:56 - 44:50 aquila There are odd communities down Green Turtle – Chelonia mydas here, discovered only in the last few Blue Whale 44:50 - 48:09 Atlantic Sailfish –Istiophorus albicans years. Communities of strange worms (TIMINGS ARE APPROXIMatE) Blue Whale – Balaenoptera musculus 3 1 Blackline Master | Planet Earth | Episode 11: Ocean Deep Viewing Questions SCREEN EDUCATION 4 1a 1 How much of the planet is covered by deep ocean? 6 When does the deep water plankton rise? 2 What is the biggest fish in the ocean? 7 Name the two big grazing fish that eat the plankton 3 What area does the white tip shark patrol for food? 8 What is the ‘marine snow’ of the deep levels? 4 What do the dolphins use to detect prey? 9 What is the unique defence of the vampire squid? 5 How deep can the shearwaters dive? SCREEN EDUCATION 10 At two miles down (just over 3.2km) what is the water pressure? 5 1b 15 What kind of coral can live in deep water? 11 What do most sea floor animals eat? 16 What do the dolphin prefer to eat? 12 What energy source can start an ecosystem down here? 17 What does the sunfish (mola mola) eat in the deeps? 18 What is the biggest animal that has ever existed? 13 What is the fastest growing marine invertebrate? 19 What do they eat? 14 How many undersea volcanoes are there? 20 What was their original population and how many are SCREEN EDUCATION now left? 6 2 Blackline Master | Planet Earth | Episode 11: Ocean Deep Ocean Deep Ecosystems SCREEN EDUCATION 7 2a The open ocean zone beyond the several centimetres in diameter in the continental shelf is called the pelagic weeks before they sink to the abyssal zone. It is then divided into sub-zones plains. based on depth. The first thing to consider is whether light can penetrate This snow is the producer of the deep – if any light from the surface at all sea ecosystem where no light pene- can be detected, it is called the photic trates and what is not eaten during its zone. Below that it is totally dark and descent, becomes part of the layer of referred to as aphotic. organic waste on the sea floor which is scavenged and filtered by small The pelagic area is further divided animals. Without it, nothing could live into depth zones, each with its own permanently in the deep waters. ecosystem. This is often a function of depth, temperature and pressure at Pelagic Ecosystems the increasing depths, as well as what – Discussion Questions light can penetrate. 1. The largest predators on earth live EPIPELAGIC (Surface down to 200m). on the some of the smallest organ- Epi – surface. This is the surface zone isms. How does this work? where enough light penetrates to al- wandering across the abyssal plains 2. Whale sharks have become an low photosynthesis. Most plants and filtering out small organic particles or important ecotourism resource. animals live in this thin zone and the scavenging dead animals that sink to Why? large fish that cruise long distances, the floor. 3. The dolphins and shearwaters like sharks and sailfish are usually seem to work together to catch found here. HADOPELAGIC (Deep ocean trench- small fish. Are they competing or es in the sea floor). co-operating? MESOPELAGIC (200m to 1,000m Hades – hell, the ancient Greek un- 4. Deep water animals often seem to deep). derworld. Mostly unexplored and with have bizarre and outrageously ugly Meso – middle. This is the zone where little life. shapes and adaptations. How can the light gets increasingly dim and we explain this? plant growth – photosynthesis is im- The bottom three zones are very 5. Photoluminescence is a strange possible. Phytoplankton – microscopic similar and are almost lifeless except adaptation and is used by terres- plants cannot grow so the ecosystem around any source of energy like a trial and marine animals. How does has to live on other materials such as hydrothermal vent – black smoker.