Month: August 2019

A chimppig hybrid origin for humans

first_img Chimps use touches and noisy gestures when trying to get another chimps attention, researcher finds © 2013 Phys.org Citation: A chimp-pig hybrid origin for humans? (2013, July 3) retrieved 18 August 2019 from https://phys.org/news/2013-07-chimp-pig-hybrid-humans.html Jul 11, 2013: Jimmy Kimmel Live – Human Species Created From Pigs and Chimps Comparison of human and chimp chromosomes. Credit: science.kqed.org/quest/2008/05/12/chromosome-fusion-chance-or-design/ It is not yet clear if or when genetic data might support, or refute, our hybrid origins. The list of anatomical specializations we may have gained from porcine philandering is too long to detail here. Suffice it to say, similarities in the face, skin and organ microstructure alone are hard to explain away. A short list of differential features, for example, would include, multipyramidal kidney structure, presence of dermal melanocytes, melanoma, absence of a primate baculum (penis bone), surface lipid and carbohydrate composition of cell membranes, vocal cord structure, laryngeal sacs, diverticuli of the fetal stomach, intestinal “valves of Kerkring,” heart chamber symmetry, skin and cranial vasculature and method of cooling, and tooth structure. Other features occasionally seen in humans, like bicornuate uteruses and supernumerary nipples, would also be difficult to incorporate into a purely primate tree.McCarthy has done extensive research into the broader issues, and shortcomings, of our currently incomplete theory of evolution. As the increasing apparent, magnificent, speed with which morphological change can occur continues to present itself for us to comprehend, the standard theory of random mutation followed by slow environmental selection, seems to stall. In my own opinion, female choice undoubtedly provides much of the functional “speed-up” we observe, but other mechanisms of mutation, or pathways for acquired characteristics to be fed back to the gonads (through retroviral transfer?), now need to be considered anew. The role of hybridization in driving morphological change, as McCarthy has observed time and time again, particularly in his studies of avian species (Oxford University Press, 2006), may be the most powerful mechanism of all.Follow-up story: Human hybrids: a closer look at the theory and evidencecenter_img Explore further Generally speaking, interspecies hybrids—like mules, ligers (lion-tiger hybrids), or zedonks (zebra-donkey hybrids)—are less fertile than the parents that produced them. However, as McCarthy has documented in his years of research into hybrids, many crosses produce hybrids that can produce offspring themselves. The mule, he notes, is an exceptionally sterile hybrid and not representative of hybrids as a whole. When it comes time to play the old nuclear musical chairs and produce gametes, some types of hybrids do a much better job. Liger females, for example, can produce offspring in backcrosses with both lions and tigers. McCarthy also points out that fertility can be increased through successive backcrossing with one of the parents, a common technique used by breeders. In the case of chimp – pig hybridization, the “direction of the cross” would likely have been a male boar or pig (Sus scrofa) with a female chimp (Pan troglodytes), and the offspring would have been nurtured by a chimp mother among chimpanzees (shades of Tarzan!). The physical evidence for this is convincing, as you can discover for yourself with a trip over to macroevolution.net.When I asked McCarthy if he could give a date estimate for the hybridization event, he said that there are a couple broad possibilities: (1) It might be that hybridization between pigs and apes produced the earliest hominids millions of years ago and that subsequent mating within this hybrid swarm eventually led to the various hominid types and to modern humans; (2) separate crosses between pigs and apes could have produced separate hominids (and there’s even a creepy possibility that hybridization might even still be occurring in regions where Sus and Pan still seem to come into contact, like Southern Sudan).This latter possibility may not sound so far-fetched after you read the riveting details suggesting that the origin of the gorilla may be best explained by hybridization with the equally massive forest hog. This hog is found within the same habitat as the gorilla, and shares many uncommon physical features and habits. Furthermore, well-known hybridization effects can explain many of the fertility issues and other peculiarities of gorilla physiology. (Phys.org) —These days, getting a Ph.D. is probably the last thing you want to do if you are out to revolutionize the world. If, however, what you propose is an idea, rather than a technology, it can still be a valuable asset to have. Dr. Eugene McCarthy is a Ph.D. geneticist who has made a career out of studying hybridization in animals. He now curates a biological information website called Macroevolution.net where he has amassed an impressive body of evidence suggesting that human origins can be best explained by hybridization between pigs and chimpanzees. Extraordinary theories require extraordinary evidence and McCarthy does not disappoint. Rather than relying on genetic sequence comparisons, he instead offers extensive anatomical comparisons, each of which may be individually assailable, but startling when taken together. Why weren’t these conclusions arrived at much sooner? McCarthy suggests it is because of an over-dependence on genetic data among biologists. He argues that humans are probably the result of multiple generations of backcrossing to chimpanzees, which in nucleotide sequence data comparisons would effectively mask any contribution from pig. 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

New limit to the ChurchTuring thesis accounts for noisy systems

first_imgCredit: Public Domain Citation: New limit to the Church-Turing thesis accounts for noisy systems (2015, September 10) retrieved 18 August 2019 from https://phys.org/news/2015-09-limit-church-turing-thesis-accounts-noisy.html Alan Turing’s legacy is even bigger than we realise © 2015 Phys.org (Phys.org)—The question of what a computer is capable of, and what it is not, has intrigued computer scientists since the 1930s, when Alonzo Church and Alan Turing began investigating the capabilities and limits of computers. In a new study, researchers have explored the computing abilities of noisy physical systems, which are those that are disturbed by random fluctuations. Journal information: Physical Review Letters 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. While previously it has seemed that physical systems may violate the Church-Turing thesis—a conjecture that in a sense defines a computer—here the researchers show that this is not the case for noisy systems due to a new computing limit. The results could have implications for designing super-Turing computers, or “hypercomputers,” which are hypothetical devices that outperform all existing computers.The researchers, Professor Mark Braverman and graduate student Jonathan Schneider at Princeton University, along with Assistant Professor Cristóbal Rojas at the Andrés Bello National University in Santiago, Chile, have published a paper on noise in computing in a recent issue of Physical Review Letters.”The greatest significance of the study is introducing a new quantitative way of thinking about noise as it affects a dynamical system when the dynamical system is being viewed or used as a computer,” Braverman told Phys.org.As the researchers explain, the presence of noise in a physical system can lead to unpredictable behavior that seems to be incomputable. If this is the case, it would violate the Church-Turing thesis.”The physical interpretation of the 1930s Church-Turing thesis asserts that a physical system cannot be harnessed to perform computations that cannot be performed (in principle) by a standard computer,” the scientists explained. “Yet, it is well-known that even basic physical laws can give rise to chaotic and unpredictable behavior. In some cases, the long-term or steady-state features of such systems can be mathematically proven to not be computable. This seemingly defies the Church-Turing thesis, which implies that all physically realizable systems can be simulated by a computer.”In the new study, however, the researchers show that computing the behavior of noisy systems is actually relatively straightforward, and therefore noisy systems are not capable of performing very complex computations. “In this paper, we show that the introduction of a small amount of noise into physical systems allows their equilibrium behavior not only to be computed, but even computed relatively efficiently,” the scientists wrote. To explain why this works, the researchers presented a new limitation on the ability of physical systems to perform computation: their memory. To formulate this so-called “space-bounded Church-Turing thesis” (SBCT), the researchers presented a new definition of memory for physical systems as “the maximum amount of information the evolving system can preserve per time step.” Using this definition, they showed that a noisy physical system with a given amount of memory can be simulated by a computer that is limited to roughly the same amount of working memory as that of the physical system.The researchers also showed that the SBCT holds even if a computer has an infinite amount of time to try to solve a problem. The new limitation is not the first variation of the original Church-Turing thesis, but it is different from most other variations in that time is not a limiting factor. The memory-based limit is of course not the only limit on computing ability—for instance, the complexity of a system is another limit, and often a more stringent one than memory. One advantage of the memory-based limit, however, is that it is generally much easier to estimate a system’s amount of memory than other properties, such as complexity.”The main usefulness of the results is in giving us a relatively simple estimate on the computational power of systems,” Braverman said. “Such an estimate is useful when thinking about proposals for super-Turing computation devices.”Super-Turing computation devices, also called “hypercomputers,” are hypothetical devices that compute functions that a Turing machine—or any computer available today—cannot. Since these functions are considered incomputable in the Church-Turing sense, super-Turing devices would either need to have an unbounded memory or otherwise circumvent the thesis. Along with exploring super-Turing computers, the researchers also plan to further investigate the SBCT at a deeper level.”The most interesting direction is further refining and understanding the notion of ‘memory’ of a general dynamical system,” Braverman said. “Another obvious direction is finding further evidence for or against the SBCT. Evidence against would be particularly exciting, since it would point at devices that can overcome their apparent information-theoretic limitations.” Explore further More information: Mark Braverman, Jonathan Schneider, and Cristóbal Rojas. “Space-Bounded Church-Turing Thesis and Computational Tractability of Closed Systems.” Physical Review Letters. DOI: 10.1103/PhysRevLett.115.098701last_img read more

All food and all play

first_imgFood should always be an experience. And after when we finally got to Benihana (Epicuria, Nehru Place) after days of planning it, those guys took it the ‘ninja’ level (for the want of a better word).We were seated at one end of their community tables (ones that can seat about eight; they also have private tables for four), sharing it with other two diners who sat on the other. With the hot plate open right in the middle of the table – the stage was set. Also Read – ‘Playing Jojo was emotionally exhausting’While the starters we ordered arrived at the table, our chef for the night – Jonathan took over the table. The main ingredient to an incredible time in Benihana is the ‘dinner show’. We call it so because it is no less than a crazy magical act that ends with you tucking in some very, very good food.All your main orders get cooked right in front of your eyes – on the table. Right from the vegetables to the rice (or noodles), the meat and the fish – Chef Jonathan whipped up a storm as we watched fascinated. With the crazy knife tricks to chopping all up at breathless speed and livening everything up with his non-stop conversation and jokes, our chef had us watching it all fascinated. Another great thing of being able to see your food get cooked in front of you is the fact that you can tell the chef exactly how you want it – and he will ask. So while my friend wanted her lamb medium rare, I wanted it well done – so there we had it, made as we wanted – on the table. Ask the chef to up the spice or keep it mild – your call, your food. Also Read – Leslie doing new comedy special with NetflixIt is mad fun and there isn’t a single dull moment in the restaurant as diners keep walking in, joining you at the table or celebrate anniversaries (the guys in Benihana will sing you an anniversary song in Japanese!). To make the best of it – go in a big group and take over an entire table, but then it is also good fun when you start talking to fellow diners about food and they start recommending things you should eat there. One of the diners at our table to us that he had just recovered from a bad reaction to prawns that landed him in the ICU, so while we encouraged us to binge on sea food (asking us to be careful all along), he played safe with the chicken and lamb. Be rest assured that no matter what you pick from their extensive menu, it is going to be quite perfect. Benihana is a very old name in authentic Teppanyaki grill eatery and they stay true to their legacy. A meal for two comes to Rs 3500 (plus taxes) at the property – head over!last_img read more

Go the baked way

first_imgOne of the finest five-star hotels of Delhi, Jaypee Vasant Continental takes pride in introducing its newest approach towards an absolutely healthy and fat-free menu for its dear customers. It brings in the concept of dried and baked dishes under its successful and popular venture – Eggspectation, but at the same time, it keeps in mind the foodies who hate the boring and hackneyed stuff and are ever-ready to give up on their health if they find anything appealing and interesting to savour. Executive Chef Avinash Jha has taken the matter into full consideration as for majority of the crowd- baked and dried dishes do not satisfy the craving for proper food, they always look up for options that are loaded with great taste and well if it cuts out on the amount of fat that is bound to enter into their body, there is nothing like it! Also Read – ‘Playing Jojo was emotionally exhausting’Eggspectation at Jaypee Vasant Continental strongly abides by the Canadian dining concept- it serves mostly egg dishes with almost 170 vegetarian and non-vegetarian delicacies to grace the menu card. The 24-Hrresto-café is coupled with impressive interiors and an interactive kitchen. Eggspectation’s vibrancy and flamboyance will make you come back again and again. Live music adds to the extravagance of the out-of-the-world dining experience.Some of the must-try dishes from Eggspectation’s newly modified menu card is the Bacon wrapped prawn with sun-dried apple, baked aubergine and pepper timble with vinegar onions, sunburned lamb and pepper satay with balsamic glazed vegetables, sun-cured roulade with pickled beetroot and dried onions.The Baked food trail will be on from July 17 to 26 at Eggspectation, Jaypee Vasant Continental, New Delhi. The timing for lunch is 12.30 pm – 3.00 pm and dinner  is 7.30 pm – 12.00 am starting at Rs 629 plus taxes.last_img read more

A film will find its own audience Srijit Mukherji

first_img

In movies, we enter a world that’s entirely the reflection of a director’s imagination, and there are only a few who can strike the right chord, making them linger on our minds even after the usual duration. Having drawn inspiration from a variety of fields such as literature, painting, movies, and music, he has emerged as one of the most innovative filmmakers of the age who managed to enthrall us with his very first film ‘Autograph.’ Mukherji has changed the course of Bangla film industry with films like Jaatishwar, Baishe Srabon, Chotushkone, Rajkahini, Hemlock Society, Mishawr Rawhoshyo among several others and has given his audience the scope to reflect on cinema that goes beyond the 70 mm screen.last_img