These Crabs Can Grow Up To 3 Feet And Hunt Birds, A Biologist's Video Proves

Agencies
November 13, 2017

Nov 13: There's a theory that giant crabs overwhelmed Amelia Earhart, dismembered her and carried her bones underground.

Speculative, at best. Sounds crazy, we know.

But so has almost every other horrifying rumor about the so-called coconut crabs - until science inevitably proves them true.

They grow to the size of dogs. They climb trees, and tear through solid matter with claws nearly as strong as a lion's jaws.

And now, finally, we have video evidence that the crabs - thousands strong on one island - can scale trees and hunt full-grown birds in their nests.

"It would at first be thought quite impossible for a crab to open a strong cocoa-nut," Charles Darwin once wrote, as that father of evolutionary biology recounted stories of a "monstrous" arthropod said to roam an island in the Indian Ocean.

"The crab begins by tearing the husk, fibre by fibre, and always from that end under which the three eye-holes are situated," Darwin wrote. "When this is completed, the crab commences hammering with its heavy claws on one of the eye-holes till an opening is made."

But Darwin would go no further than that. The genius who championed life's endless forms gave no credence to reports that these fierce giant crabs could also climb trees.

In the decades to come, of course, coconut crabs would be photographed not only climbing trees but hanging from them like enormous hard-shell spiders. Researchers in our own century once left them a small pig carcass to see what would happen, Smithsonian Magazine wrote.

The crabs quickly disappeared the pig.

Now we know they are the largest invertebrate to walk the earth - more than three feet long, pincer to pincer, with claws so strong that a researcher once tried to measure the force, and described it as "eternal hell" after a coconut crab caught his hand.

But what, wondered Mark Laidre, do they eat?

"Few studies of this remarkable animal's behavior have been undertaken since Darwin's Beagle voyage," the Dartmouth College biologist wrote in a paper published this month.

That they ate coconuts had been established long ago, of course. And like other crabs, Laidre wrote, they were known to scavenge off corpses (leaving aside whether Amelia Earhart was one of them.)

But what else did they eat? Laidre was fascinated by a story told to him by a witness in 2014, from the Chagos Archipelago in the middle of the Indian Ocean.

"An adult red-footed booby had landed near the entrance to a coconut crab's burrow," Laidre recounted. "As the bird stood there, the crab slowly emerged from its underground lair, approaching the bird from behind. The crab then grabbed the bird by one leg and dragged it, struggling, back into its burrow."

The witness never saw the bird again.

In all his years of research, Laidre wrote, he had never seen a crab prey on any animal besides - rarely - another crab. So two years after the reported disappearance of the booby, the biologist set off for the Chagos to find out if giant crabs really stalked birds.

The archipelago's largest island is ring-shaped, and three smaller, uninhabited islands sit in its mouth. Laidre carefully surveyed each one.

Dozens of birds took flight the moment he stepped onto one of the smaller islands, he wrote, and "continued circling overhead as I undertook my transect along the island's length."

Nests and eggs covered the rocky beach of this island - and there was not a single giant crab in sight.

But on the other two small islands, Laidre wrote, he saw dozens of coconut crabs and few nests. He wrote in his paper of an evolutionary theory called "landscapes of fear" - that few animals will dare make homes in places dominated by predators.

When he surveyed the fourth island, Laidre wondered if the crabs simply ruled it.

"I counted over 1,000 coconut crabs in single [9-mile] transects but did not observe even one ground-nesting bird," Laidre wrote. All the nests were high up in the trees, and cracked coconuts littered the ground.

After about a month on the island, in February of 2016, he investigated a giant crab's underground lair.

"Deep inside the crab's burrow was the carcass of a nearly full-grown red-footed booby," he wrote.

This was Laidre's first sign that the stories might be true, that giant crabs really were hunting birds.

He had his proof a month later.

"In the middle of the night," Laidre wrote, "I observed a coconut crab attack and kill an adult red-footed booby."

"The booby had been sleeping on a low-lying branch, less than a meter up the tree," he wrote. "The crab slowly climbed up."

He watched the crab take the bird's wing in its great claws. He watched it break the bones beneath the feathers.

Then bird fell to the ground, Laidre wrote, and the crab descended in pursuit.

About 90 seconds of what happened next is now documented in the researcher's video, if you care to watch.

The booby pecks twice at the crab, and might as well have hit hardwood. Futile.

It makes a sort of squawking, croaking sound, over and over, at least a dozen times. Then its head rolls back and the bird simply breaths, unprotesting, as the crab's claws sink into its down.

"Five more coconut crabs came to the site within 20 minutes, likely cueing in on the blood," Laidre wrote. They tore it to pieces and took it away, and now yet one more thing is known about the giant coconut crabs of the Indian and Pacific oceans.

That the crabs cannot swim well, Laidre wrote, may be why one of the four islands still belonged to the birds.

But the biologist wondered what would happen if just one crab were taken there, in the interests of science.

A juvenile would probably be overwhelmed and eaten by birds, he wrote. But "an adult crab may wreak havoc."

"Further research could experimentally test these ideas, although important ethical considerations would obviously arise," Laidre wrote. "The birds would need to be protected."

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Agencies
June 9,2020

Soon, you may be able to withdraw cash from an ATM without touching any part of the machine. AGS Transact Technologies, a provider of cash and digital payment solutions and automation technology, on Monday said it has successfully developed and tested a touchless ATM solution in light of the COVID-19 pandemic.

The ‘contactless' solution, currently under demo at interested banks, enables a customer to perform all the steps required to withdraw cash from an ATM using the mobile app itself. 

The customer simply has to scan the QR code displayed on the ATM screen and follow the directions on their respective bank's mobile application. 

This includes entering the amount and mPIN required to dispense the cash from the ATM machine. 

According to the company, the QR code feature makes cash withdrawals quicker and more secure, and negates the chances of compromising the ATM Pin or card skimming.

"The new Touchless ATM solution is an extension of the flagship QR Cash solution which ensures safety of the users and will provide a seamless cash withdrawal experience with enhanced security," said Ravi B. Goyal, Chairman and MD, AGS Transact Technologies Ltd.

With minimum investment, the banks can enable this solution for their ATM networks by upgrading the existing software.

AGSTTL has so far installed, maintained and managed a network of over 72,000 ATMs across the country and also provides customised solutions to leading banks. 

The company earlier introduced UPI-QR based Cash withdrawal solution in partnership with Bank of India. 

This is how the solution works.

Open the Bank mobile application on your smartphone and select QR Cash Withdrawal. Enter the amount you wish to withdraw on the mobile app and scan the QR code on the ATM screen.

Next, confirm the amount by clicking on ‘proceed' in the app and enter the mPin to authenticate the transaction. Now collect the cash and receipt and you are done.

"The seamless, cardless and touchless withdrawal method is designed to provide easy transaction flow, without the need to touch the ATM screen or enter the pin," said Mahesh Patel, President and Group Chief Technology Officer, AGS Transact Technologies.

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Agencies
July 4,2020

The Mars Colour Camera (MCC) onboard ISRO's Mars Orbiter Mission has captured the image of Phobos, the closest and biggest moon of Mars.

The image was taken on July 1 when MOM was about 7,200 km from Mars and 4,200 km from Phobos.

"Spatial resolution of the image is 210 m.

This is a composite image generated from 6 MCC frames and has been color corrected," ISRO said in an update along with the image.

Phobos is largely believed to be made up of carbonaceous chondrites.

According to ISRO, "the violent phase that Phobos has encountered is seen in the large section gouged out from a past collision (Stickney crater) and bouncing ejecta."

"Stickney, the largest crater on Phobos along with the other craters (Shklovsky, Roche & Grildrig) are also seen in this image," it said.

The mission also known as Mangalyaan was initially meant to last six months, but subsequently ISRO had said it had enough fuel for it to last "many years."

The country had on September 24, 2014 successfully placed the Mars Orbiter Mission spacecraft in orbit around the red planet, in its very first attempt, thus breaking into an elite club.

ISRO had launched the spacecraft on its nine-month- long odyssey on a homegrown PSLV rocket from Sriharikota in Andhra Pradesh on November 5, 2013.

It had escaped the earth's gravitational field on December 1, 2013.

The Rs 450-crore MOM mission aims at studying the Martian surface and mineral composition as well as scan its atmosphere for methane (an indicator of life on Mars).

The Mars Orbiter has five scientific instruments - Lyman Alpha Photometer (LAP), Methane Sensor for Mars (MSM), Mars Exospheric Neutral Composition Analyser (MENCA), Mars Colour Camera (MCC) and Thermal Infrared Imaging Spectrometer

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Agencies
June 17,2020

In a bid to help tackle rise in domestic violence during the social distancing times in India, Twitter on Wednesday launched a dedicated search prompt to serve information and updates from authoritative sources around domestic violence.

Twitter has partnered with the Ministry of Women and Child Development the National Commission for Women in India to expand its efforts towards women.

The search prompt will be available on iOS, Android and on mobile.twitter.com in India, in both English and Hindi languages, the company said in a statement.

Data shows that since the outbreak of Covid-19, violence against women and girls has intensified in India and across the globe.

"We recognise collaboration with the public, government and NGOs is key to combating the complex issue of domestic violence. Accessing reliable information through this search prompt could be a survivor's first step towards seeking help against abuse and violence," said Mahima Kaul, Director, Public Policy, India and South Asia, Twitter.

Every time someone searches for certain keywords associated with the issue of domestic violence, a prompt will direct them to the relevant information and sources of help available on Twitter.

This is an expansion of Twitter's #ThereIsHelp prompt, which was specifically put in place for the public to find clear, credible information on critical issues.

The feature will be reviewed at regular intervals by the Twitter team to ensure that all related keywords generate the proactive search prompt, said the company.

Violence against women and girls across Asia Pacific is pervasive but at the same time widely under reported.

"In fact, in many countries in our region, the number is even greater, with as many as 2 out of 3 women in some countries reporting experiences of violence," added Melissa Alvarado, UN Women Asia Pacific Regional Manager on Ending Violence against Women.

Rekha Sharma, Chairperson, the NCW, said: "With social distancing norms in place, several women are unable to contact their regular support systems. This initiative by Twitter will provide big support to the survivors, who would otherwise be easily isolated without access to relevant information and help".

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