Sailfish found to use group hunting technique to capture more sardines

first_img Citation: Sailfish found to use group hunting technique to capture more sardines (2016, November 2) retrieved 18 August 2019 from https://phys.org/news/2016-11-sailfish-group-technique-capture-sardines.html More information: James E. Herbert-Read et al. Proto-cooperation: group hunting sailfish improve hunting success by alternating attacks on grouping prey, Proceedings of the Royal Society B: Biological Sciences (2016). DOI: 10.1098/rspb.2016.1671AbstractWe present evidence of a novel form of group hunting. Individual sailfish (Istiophorus platypterus) alternate attacks with other group members on their schooling prey (Sardinella aurita). While only 24% of attacks result in prey capture, multiple prey are injured in 95% of attacks, resulting in an increase of injured fish in the school with the number of attacks. How quickly prey are captured is positively correlated with the level of injury of the school, suggesting that hunters can benefit from other conspecifics’ attacks on the prey. To explore this, we built a mathematical model capturing the dynamics of the hunt. We show that group hunting provides major efficiency gains (prey caught per unit time) for individuals in groups of up to 70 members. We also demonstrate that a free riding strategy, where some individuals wait until the prey are sufficiently injured before attacking, is only beneficial if the cost of attacking is high, and only then when waiting times are short. Our findings provide evidence that cooperative benefits can be realized through the facilitative effects of individuals’ hunting actions without spatial coordination of attacks. Such ‘proto-cooperation’ may be the pre-cursor to more complex group-hunting strategies. Most people have likely seen sailfish on television—they have long, pointed bills and fan-like fins on their backs and are generally seen jumping out of the water after being hooked on a fisherman’s line. In this new effort, the researchers were interested in the hunting habits of the fish, so they sailed around off the coast of Mexico looking for frigate birds that tend to congregate over hunting areas. Once a hunt was found, the researchers watched and filmed the action.Studying what they recorded, the researchers found that the sailfish hunted in groups surrounding a school of sardines, but unlike other group hunters, their attacks were not coordinated—instead, individuals would simply swim into the school of sardines and then arrive at the other side. Such forays, the researchers found, resulted in a catch just 24 percent of the time, but, they also found that such attacks also resulted in injuring a sardine approximately 95 percent of the time, which made it easy for the sailfish hanging around in the crowd to grab them. The overall result, the team reports, was a higher per capita capture than would have occurred had the sailfish all hunted alone with less energy expended for all of the participants. The researchers also found that individual sailfish that opted to take the “free riding” strategy (never actually swimming into the sardine group) only worked if the cost of attacking was high and waiting times were short. They also found that both the size of the sardine group and the sailfish group varied in size—from many members to just a few. Interestingly, the team also noted that the sailfish did not appear to take turns dashing into the sardine mix; instead, attacks occurred at random. Explore further Field study shows how sailfish use their bill to catch fish Journal information: Proceedings of the Royal Society Bcenter_img An Indo-Pacific sailfish raising its sail. Credit: Wikipedia/GFDL 1.2 © 2016 Phys.org (Phys.org)—An international team of researchers has found that sailfish use a unique form of group hunting to improve the catch for all involved. In their paper published in Proceedings of the Royal Society B, the group describes their adventures studying the hunting behavior of the fish off the coast of Mexico and why they believe the behavior might be an example of social engagement that could lead to more complex cooperative strategies in other groups of animals. This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.last_img read more

Theatre for the blooming buds

first_imgWith dollops of fun, acting and lessons on life skills, summer vacations are about to get exciting. All you 8-15 year olds, First Act  is here in town. Get onto the bandwagon to learn essential life skills over 15 days this summer. Enthusing you with confidence through the medium of theatre and experimental methods practiced all over the world, this team has a plan to set you ahead of your times. Battle out your inhibitions and stage fright with a team of mentors who have a flair for acting. Rakesh Jasrotia and Vaishali Chakravarty, the two renowned artistes spearheading First Act, have devised a module to encourage teamwork and enhance self image to culminate all your sweat to a short performance at the end of the program. Give wings to your imagination and skills and mark in these dates.last_img read more

Postnatal care in Monsoon

first_imgMonsoon is here with its joyous rains, humid weather and the ineluctable happiness of a petrichor. But with it comes the added health risk and water borne diseases whose number rises manifold in these months of monsoon. Small children are at a higher risk of catching these diseases due to weaker and still developing immunity systems. So, parents of infants should take special care to prevent these infections. Here are 4 precautions you must take to pre-empt these diseases. Also Read – Add new books to your shelfChanging the diaper more regularly: Moisture is one of the major components that help in the growth of harmful germs. Changing diapers orderly will help you in maintaining good hygiene.Sustaining a clean and dry environment in the house with regular mopping, checking for any water blockage that might initiate growth of harmful organisms and mosquitoes. Small steps like washing the baby’s clothes separately, cleaning their toys with disinfectant solutions may prove to be really beneficial for your baby. Also Read – Over 2 hours screen time daily will make your kids impulsiveDiseases like Cholera and typhoid can be easily prevented by saving the baby’s food and water from contamination. Fresh food is the best for your child’s growth.Always dress your baby in loose cotton clothing to avoid unnecessary itching. This irritation can make your baby very cranky. It’s better to be on the safe side and dress them in comfortable clothing.Other small things that can save you the horror of monsoon diseases are mosquito repellents. They’re available in small badges which can be attached to a baby’s clothes for easy use. Geetika Trehan, mother of an 8-month-old says, “I prevent taking him to malls and crowded places. Parks and areas with water are a strict no-no during monsoon.” Crowded places are a hub of infections which can be very dangerous for your little one. It’s best to take precautions and not take them there than to pay a price. Dr Raj Chakravarty (MD-Obstetrics and Gynaecology) suggests some basic Dos and Don’ts for new mothers during monsoon. 1. Take a high protein diet including eggs, fish, chicken, pulses and milk. Foods like Chana and Rajma should be strictly avoided as they might cause gastric problems to the baby. A diet rich in fibre and green vegetables should be taken to assure good health.2. Plenty of fluid intakes is a must to avoid urinary tract infections common in new mothers, especially during rainy season. Fluids also help in easy lactation which is beneficial for the baby. 3. A new born should only be breastfed during monsoon otherwise they’ll be at a high risk of gastroenteritis and fungal infections.4. As a new mother, you must try and avoid constipation by going for regular walks and take iron, calcium and vitamin supplements. They’ll ensure you and your baby’s well-being.A recently launched European brand ‘U-grow’ is making life easy for new parents. With its work reducing machines and childcare products like ‘nasal aspirator’ that helps in the suction of nasal secretions which makes it easy for a child to breath especially during illnesses and humid weather since a child under 1 year of age can only breathe through their nose. Another really efficient product is the breast pump. It’s a really logical solution of time to time and hygienic breast feeding for working mothers. Now, you can store milk in these air tight breast pumps for your baby to consume throughout the day without risking their health. One of their must have monsoon products is the ‘hot humidifier’ that will help you in maintaining optimum humidity in your room that will suit your child.last_img read more

Ford Is Developing a Fully Electric FSeries Pickup Truck

first_img Ford is taking steps to future-proof its business by developing not just a hybrid, but a fully electric pickup truck. Jim Farley, Ford president of global markets, has announced at an event in Detroit that the automaker is electrifying the F-series. The company has been working on a hybrid version of the F-150 since 2015, but this is a completely different project. Unfortunately, Farley didn’t confirm which particular model is going to get the EV treatment.It wouldn’t come as a surprise if Ford is also making a pure electric version of the F-150, though, seeing as it is one of the most recognizable and best-selling American vehicles. The iconic pickup accounts for around a third of the automaker’s sales in the U.S. and has a long history behind it, dating back to 1975. It’s the perfect model for this project, which feels like a natural development following Ford’s investments in the EV market.By developing an electric pickup, Ford is hoping that it’ll be able to keep up with rivals that are also creating their own. A startup called Rivian unveiled its own take on the category in 2018, and even the vastly more popular Tesla is planning to conjure up an electric pickup truck of its own within the next few years. Attend this free webinar and learn how you can maximize efficiency while getting the most critical things done right. Free Webinar | Sept 5: Tips and Tools for Making Progress Toward Important Goals This story originally appeared on Engadget 2 min read January 17, 2019 Register Now »last_img read more

Google Brains Universal Transformers an extension to its standard translation system

first_imgLast year in August Google released the Transformer, a novel neural network architecture based on a self-attention mechanism particularly well suited for language understanding. Before the Transformer, most neural network based approaches to machine translation relied on recurrent neural networks (RNNs) which operated sequentially using recurrence. In contrast to RNN-based approaches, the Transformer used no recurrence, instead it processed all words or symbols in the sequence and let each word attend the other word over multiple processing steps using a self-attention mechanism to incorporate context from words farther away. This approach led Transformer to train the recurrent models much faster and yield better translation results than RNNs. “However, on smaller and more structured language understanding tasks, or even simple algorithmic tasks such as copying a string (e.g. to transform an input of “abc” to “abcabc”), the Transformer does not perform very well.”, says Stephan Gouws and Mostafa Dehghani from the Google Brain team. Hence this year the team has come up with Universal Transformers, an extension to standard Transformer which is computationally universal using a novel and efficient flavor of parallel-in-time recurrence. The Universal Transformer is built to yield stronger results across a wider range of tasks. How does the Universal Transformer function The Universal Transformer is built on the parallel structure of the Transformer to retain its fast training speed. It has replaced the Transformer’s fixed stack of different transformation functions with several applications of a single, parallel-in-time recurrent transformation function. Crucially, where an RNN can process a sequence symbol-by-symbol (left to right), the Universal Transformer will process all symbols at the same time (like the Transformer), but then refine its interpretation of every symbol in parallel over a variable number of recurrent processing steps using self-attention. This parallel-in-time recurrence mechanism is both faster than the serial recurrence used in RNNs, making the Universal Transformer more powerful than the standard feedforward Transformer. Source: Google AI Blog At each step, information is communicated from each symbol (e.g. word in the sentence) to all other symbols using self-attention, just like in the original Transformer. However, now the number of times transformation will be applied to each symbol (i.e. the number of recurrent steps) can either be manually set ahead of time (e.g. to some fixed number or to the input length), or it can be decided dynamically by the Universal Transformer itself. To achieve the latter, the team has added an adaptive computation mechanism to each position which will allocate more processing steps to symbols that are ambiguous or require more computations. Furthermore, on a diverse set of challenging language understanding tasks the Universal Transformer generalizes significantly better and achieves a new state of the art on the bAbI linguistic reasoning task and the challenging LAMBADA language modeling task. But perhaps the larger feat is that the Universal Transformer also improves translation quality by 0.9 BLEU1 over a base Transformer with the same number of parameters, trained in the same way on the same training data. “Putting things in perspective, this almost adds another 50% relative improvement on top of the previous 2.0 BLEU improvement that the original Transformer showed over earlier models when it was released last year”, says the Google Brain team. The code to train and evaluate Universal Transformers can be found in the open-source Tensor2Tensor repository page. Read in detail about the Universal Transformers on the Google AI blog. Read Next: Create an RNN based Python machine translation system [Tutorial] FAE (Fast Adaptation Engine): iOlite’s tool to write Smart Contracts using machine translation Setting up the Basics for a Drupal Multilingual site: Languages and UI Translationlast_img read more