Teacher:In this task, you are given a text of many news articles seperated by special token "|||||". Your task is to summarize them.
Teacher: Now, understand the problem? Solve this instance: Computer imagery of the 'Drowned Apostles' -- limestone sea stacks found underwater off Australia's southern coast. Credit: Rhiannon Bezore Australia's iconic tourist attraction, the Twelve Apostles, has received an unlikely boost in numbers with the discovery of five extra limestone columns hidden way below the water. 
  
 The never-before-seen sea stacks, located 6km offshore from the Great Ocean Road and 50m beneath the water's surface, were revealed during sonar mapping of the seafloor off Victoria's southern coast. 
  
 Scientists are dubbing them the "Drowned Apostles". 
  
 While the Drowned Apostles are smaller in both size and number than their more famous cousins, their existence alone is remarkable given their defiance of normal erosion rates. 
  
 It is understood to be the first time such limestone stacks have been found preserved in the ocean. 
  
 The discovery was made by PhD student Rhiannon Bezore, Associate Professor David Kennedy from the University of Melbourne's School of Geography and Deakin University's Dr Daniel Ierodiaconou, who provided the high-resolution sonar data. 
  
 "Sea stacks are always eroding, as we saw with the one that collapsed in 2005, so it is hugely surprising that any could be preserved at that depth of water," Associate Professor Kennedy said. 
  
 "They should have collapsed and eroded as the sea level rose." 
  
 Like the Twelve Apostles, the newest additions would have once been part of larger limestone sea cliff. 
  
 An underwater shot of the Drowned Apostles. Credit: Liz Rogers Photography 
  
 Ms Bezore, who made the initial discovery in the sonar data, said they probably date back 60,000 years. 
  
 "We had to check what we were seeing because no one has seen stacks submerged at this sea level before," she said. 
  
 Only a very fine balance can create sea stacks, with rock needing to be soft enough to erode quickly from a cliff but hard enough to support a rocky pillar, Dr Ierodiaconou said. 
  
 Dr Ierodiaconou's sonar data was collected using the latest advances in multi-beam sonar technology and the team are continuing to fill important knowledge gaps aboard Deakin's $650,000 research vessel "Yolla". 
  
 The data is part of a project to map the reef estate in Victoria which supports commercial fisheries for southern rock lobster and abalone. 
  
 "We are only just starting to understand the biodiversity value of these deep reefs which harbour diverse invertebrate communities, many unknown to science," he said. 
  
 Ms Bezore will present the paper at the International Coastal Symposium in Coogee, Sydney on Thursday morning. 
  
 The findings have been published in the US-based Journal of Coastal Research. 
  
 Explore further: Uncovering the secret lives of fish in marine national parks 
  
 More information: Journal of Coastal Research, dx.doi.org/10.2112/S175-119.1 
  
  ||||| Thought there were just eight of the Twelve Apostles still standing off the Great Ocean Road coastline? Think again. 
  
 Scientists have found a further five limestone stacks underwater, in a surprise discovery which probably makes the marine monoliths the world's only known limestone columns to remain preserved in the ocean. 
  
 The sea stacks, which appear to host a variety of coral and other sea life, are located in a linear formation six kilometres offshore, between Point Campbell and Peterborough. 
  
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 Link The Twelve Apostles - as seen above the watermark. Photo: Jarrod Woolley 
  
 Standing between four to six metres high and beneath 50 metres of water, the structures have been dubbed the "drowned Apostles" by scientists. 
  
 Melbourne University PhD student Rhiannon Bezore discovered the additional Apostles while doing a preliminary scan of some sonar data collected by Deakin University researcher Daniel Ierodiaconou. At first she couldn't believe it. 
  
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 "They looked suspiciously like sea stacks and I literally did a double take," she said. 
  
 "This is kind of a first because sea stacks are really temporary features that exist more on a centuries time scale." 
  
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 Link Researchers explore the surface of one of the 'drowned apostles'. Photo: Liz Rogers 
  
 However Ms Bezore said the five underwater limestone stacks are estimated to be about 60,000 years old. 
  
 "The fact that they were spotted or exist, even, is pretty surprising," she said. 
  
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 Link Tourists visiting the Twelve Apostles have only seen some of the famous limestone columns. Photo: Jarrod Woolley 
  
 Originally the drowned Apostles would have been part of the same limestone coastline as the eight exposed Apostles, which are younger. 
  
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 Link The scanned underwater limestone columns, or drowned Apostles. Photo: Rhiannon Bezore 
  
 Ms Bezore said the underwater limestone stacks probably managed to survive because they formed at a time when the sea level was rising, which allowed them to be submerged without being eroded by the waves for too long. 
  
 Dr Ierodiaconou said only certain types of rock could create sea stacks, as the material had to be hard enough to support a rocky pillar and soft enough to erode quickly and break free from the cliff face. 
  
 At up to six metres tall the drowned Apostles are notably shorter than their exposed counterparts, which stand between 30 to 40 metres tall. 
  
 When they were named the 12 Apostles in the 1920s, there were only nine in the cluster. That was reduced the eight following the dramatic collapse of one in 2005. 
  
 Ms Bezore's research, which is being supervised by David Kennedy and Dr Ierodiaconou, also established the erosion rate of the cliffs behind the Twelve Apostles for the first time. 
  
 She found the limestone was eroding at between 0.29 metres and 0.32 metres each year. 
  
 "That doesn't sounds like much but it does add up over time and a lot of erosion along that stretch of coast is episodic, so things like landslides and cliff collapse," she said. 
  
 Published in the Journal of Coastal Research, Ms Bezore will present her findings at the International Coastal Symposium in Sydney on Thursday morning. ||||| View of a portion of the ocean rock formations known as the '12 Apostles' at Port Campbell National Park in Victoria, Australia, in this file picture taken October 19, 2010. REUTERS/Clarissa Cavalheiro/Files 
  
 SYDNEY Massive underwater limestone towers have been found in line with Australia's famous '12 Apostle' ocean rock formations, in a surprise discovery that scientists said was previously thought impossible. 
  
 The five underwater columns, dubbed by scientists the 'Drowned Apostles', are around 10 meters (32 feet) tall and continue the chain of the '12 Apostles', which are up to 40 meters (130 feet) tall off the coast of the southern state of Victoria and a major tourist attraction. 
  
 It is believed the underwater towers were submerged and preserved by rapidly rising sea levels at the end of the last Ice Age around 11,000 years ago. 
  
 "This is the first time in the world we have seen underwater sea stacks. They don't last long due to erosion and according to all the textbooks they shouldn't be there," said Melbourne University geologist David Kennedy. 
  
 Sea levels are believed to have risen during peak melting points at the end of the last Ice Age, fast enough to preserve the shape of the unique rock formations which are believed to date back around 60,000 years, said Kennedy. 
  
 "They most likely used to be taller but were shaved down by the rising sea. The sea rise was so rapid the waves just went over the top and they didn't have time to knock them over," said Kennedy. 
  
 The 'Drowned Apostles' discovery was published in the Journal of Costal Research by postgraduate student Rhiannon Bezore, who along with Kennedy, stumbled upon the find when analyzing previously unstudied sonar mapping of the area. 
  
 A major draw-card for tourists along Victoria's Great Ocean Road, the '12 Apostles' have had their numbers reduced over the years due to rapid erosion. The most recent collapse in 2009 left only seven remaining columns. 
  
 (Reporting by Jarni Blakkarly; Editing by Michael Perry) |||||
Student:
One of Australia's most beloved attractions is its 12 Apostles—ancient rock formations poking out of the waves off Victoria's coast. Scientists say they're in awe after discovering five "Drowned Apostles" in a linear formation hiding 160 feet underwater a few miles offshore. Melbourne University PhD student Rhiannon Bezore was studying a sonar scan of the area when she spotted what "looked suspiciously like sea stacks and I literally did a double take," she tells the Sydney Morning Herald. Colleague David Kennedy understands why. "This is the first time in the world we have seen underwater sea stacks," the geologist tells Reuters. "They don't last long due to erosion and according to all the textbooks they shouldn't be there." Scientists believe the limestone columns have been around for 60,000 years—longer than the 12 Apostles, of which only eight remain—but broke apart from the cliff face, per a release. Kennedy believes the structures were drowned so quickly by rising seas around the end of the last ice age 11,000 years ago that "the waves just went over the top and they didn't have time to knock them over." The waves may have shortened the structures, though: The largest stretches about 32 feet high, while its neighbors closer to shore reach up to 130 feet high, per Reuters. The 12 Apostles are easier to visit since they don't require a wet suit, but they won't be around forever. Bezore warns they're eroding about 1 foot per year. (Scientists claim a new discovery about Stonehenge.)