Egg-Shape Evolution Theory Cracks Under Pressure

first_imgTouted as an evolutionary explanation for bird egg shapes, a new hypothesis celebrating natural selection falls like Humpty Dumpty under a gentle breeze of questioning.I think that, if required on pain of death to name instantly the most perfect thing in the universe, I should risk my fate on a bird’s egg. —Thomas Wentworth Higginson, 1862Natural selection is the hero of a paper in Science Magazine about bird eggs, and was sure to make that clear in its write-up. “How eggs got their shapes: Adaptations for flight may have driven egg-shape variety in birds,” the bold headline announces. Read further in this article classified under evolution, and you see that a Professor of Organismic and Evolutionary Biology from Harvard used an evolutionary framework to determine the “implications of egg shape in an evolutionary and ecological setting.” This egg story is drenched in evolutionary seasoning, to make sure the reader won’t miss the taste.And if that isn’t enough evolutionary flavor, Claire N. Spottiswoode in Science Magazine marinates the egg story in Darwin’s special brand Natural Selection Sauce. She says,The selection pressure that best explains its evolution comes from the characteristic we most associate with birds: flight.This hypothesis predicts that species under strong selection for flight-related adaptations—such as migrants and aerial insectivores—should have elliptical or asymmetric rather than spherical eggs.The authors use an index of aerodynamic wing shape as a proxy for such selection, and find that this is by far the best predictor of egg shape.Why, then, are there no hot-air balloon–shaped eggs? Not only do they appear developmentally hard to produce, but perhaps they offer no obvious selective advantage over a spherical egg: They are still inconveniently wide, with little increase in volume.Egg collecting is now deeply unfashionable and rightly illegal. But from its heyday in the late 19th to the mid-20th century, it has bequeathed to us data that can yield wonderful evolutionary insights, as Stoddard et al.‘s study underlines.Evolution. Evolution. Evolution. Got it? Eggs evolved by natural selection, and Science shows how. Darwin’s theory explains “an old mystery in natural history,” says. No smart person should ever doubt evolution again. Look how useful evolutionary theory is to science! Spottiswoode says,Every bird egg serves the same function: to protect and nourish the offspring within while it grows from two cells to a fully formed chick. Yet this identical function is served by a striking diversity of egg shapes. Explanations for both the origin and function of this diversity have remained little more than anecdotal. On page 1249 of this issue, Stoddard et al. marry biophysics and ecology to provide a general theory that explains how and why diverse egg shapes arose. Based on a mathematical model, the authors predict that simple changes in the forces experienced by the shell membrane as the egg develops in the female’s oviduct are sufficient to generate the observed egg-shape diversity across all birds. The selection pressure that best explains its evolution comes from the characteristic we most associate with birds: flight.One certainly can’t fault the scientific rigor of Stoddard’s team. They accessed a museum collection of almost 50,000 eggs from 1,400 bird species. They proposed a hypothesis. They used math and built a chart with ellipticity on one access and asymmetry on the other axis. They compared the positions of eggs on this chart with the flight behaviors of the species. They made predictions that were fulfilled, and covered anomalies with auxiliary explanations. They showed how their hypothesis succeeds over the “anecdotal” proposals of others. Evolution wins again!In an eggshell, the explanation goes like this: the demands of flight create selection pressure on egg shape. Spottiswoode dispenses with old theories about clutch size, the need to prevent rolling off cliffs, and other “intriguing but ultimately parochial hypotheses” to lead into the new-and-improved idea hatched by Stoddard’s team:Instead they find consistent support for a simple hypothesis. Birds are streamlined for flight. Perhaps streamlined birds need narrower eggs to negotiate their narrower pelvis, and because the only way to fit a chick into a narrower egg is to make the egg longer, elliptical or asymmetric eggs result. This hypothesis predicts that species under strong selection for flight-related adaptations—such as migrants and aerial insectivores—should have elliptical or asymmetric rather than spherical eggs. The authors use an index of aerodynamic wing shape as a proxy for such selection, and find that this is by far the best predictor of egg shape. Swifts that live almost all of their lives on the wing have elliptical eggs. Sandpipers that traverse the globe have elliptical, asymmetric eggs. Puffbirds and trogons of tropical forests that may rarely leave their territories tend to have relatively spherical eggs. So, too, do flightless ostriches, but not penguins—perhaps because they must be streamlined to “fly” underwater. Within specific taxonomic groups, additional correlations suggest that other demands, such as clutch size, do further modulate egg shape, but none applies generally across all birds. Why, then, are there no hot-air balloon–shaped eggs? Not only do they appear developmentally hard to produce, but perhaps they offer no obvious selective advantage over a spherical egg: They are still inconveniently wide, with little increase in volume.Some QuestionsCan the evolutionary answer stand up to a gentle whiff of questioning? A running theme at CEH is that natural selection is a vacuous concept masquerading as a scientific explanation. By failing to provide real concrete predictions that are testable, natural selection reduces to the Stuff Happens Law—the opposite of explanation. Whatever happens, “it evolved,” so that the explanation becomes a just-so story. Are these scientists and reporters playing make-believe again? Or have they really demonstrated the value of Natural Selection theory for science? Let’s think about it.We should note first that egg shapes are examples of microevolution. Getting a chick to develop in 21 days that can hatch and fly is the big issue for evolution; egg shape and size seem very minor by comparison. We might compare the phenomenon to a magician pulling a rabbit out of a hat. Changing the shape of the hat or the size of the rabbit doesn’t matter as much as being able to do the trick itself. Furthermore, the evolutionary story fails to rule out creation or intelligent design, because advocates of those positions are perfectly happy to see variation in egg shape for different species, and are willing to admit some degree of change over time. So far, then, we don’t see the evolutionary story deserving of privileged status.Pelican, courtesy Illustra Media.The biggest piece of evidence they adduce is the chart showing a correlation between flight behavior and egg shape. It’s an interesting pattern. Correlation, however, does not imply causation. Does the egg shape drive the female bird’s oviduct, or does the oviduct drive the egg shape? If aerodynamic efficiency makes natural selection drive egg shape, one would think it would also drive everything else about the bird, like beak shape and mass. But beaks among strong flyers vary all over the map (consider pelicans, hummingbirds, and Arctic terns). Furthermore, for good reason, females only lay eggs when they are not flying. And what about the males, who don’t have an oviduct? It’s not exactly clear why natural selection would have any influence on egg shape. How do they know the differences are not due to genetic drift or some other non-Darwinian mechanism?Hummingbird eggs, by David CoppedgeMore importantly, the scientists, and Ms Spottiswoode and the reporter, fail to apply neo-Darwinian theory correctly. They do not identify any mutation in egg shape genes that consistently appears and gets selected when a flyer needs an elliptical egg to survive and produce offspring. That should be the case if natural selection is a law of nature superior to the Stuff Happens Law. They fail to show how every other member of the population died out, such that only the individuals possessing the mutation survived to lay eggs. The explanation, in fact, sounds Lamarckian (inheritance of acquired characteristics) – certainly no less anecdotal than the preceding hypotheses. A look through the main paper reveals the authors admitting that in some respects, the preceding hypotheses made predictions about egg shape that work just as well as theirs. Wobbling between multiple conflicting variables, their flight-adaptation hypothesis reduces to speculation with a very weak empirical basis.Adding to the trouble, their phylogenetic analysis fails to find a consistent ancestry connecting flight ability to egg shape, leaving them scrambling for auxiliary hypotheses like convergence and parallel evolution. Watch the perhapsimaybecouldness index rise like a stiff breeze, threatening the stability of their hatched hypothesis:We do not suggest that a female’s flight behavior during the egg formation period directly affects egg formation, nor do we suggest that egg shape so strongly influences the flight abilities of female birds during their egg-laying period that selection has produced an aerodynamic egg. Rather, we propose that general adaptations for strong flight select for a constrained, muscular, streamlined body plan in both males and females, giving rise in the latter, directly or indirectly, to asymmetric and/or elliptical eggs. The precise physiological mechanisms by which morphological adaptations for flight might affect egg shape are unknown. However, the answer most likely lies in the two parameters highlighted by our biophysical model: egg membrane thickness variations and the differential pressure applied across the membrane, both of which are potentially shaped by selection for a streamlined body plan.Humpty Dumpty just fell. Wasn’t natural selection Darwin’s famous ‘mechanism’ to explain everything in biology? They just said the mechanisms are ‘unknown’, and only ‘might’ affect egg shape. They just said natural selection might work ‘directly or indirectly’—well, which is it? Clearly they do not know. Selection might have been ‘giving rise to’ (miracle words) “asymmetric and/or elliptical eggs,” implying that whatever influence natural selection had was general, non-specific and ambiguous. Is this an explanation, or something they find ‘most likely’ and ‘potentially’ explanatory? That’s only an opinion—a preference. Readers should make up their own minds about the strength of the evidence, not kowtow to the authors’ bluffing about the success of their hypothesis.In short, their hypothesis crashes to the ground right during the Darwin celebration, leaving a scrambled mess of just-so storytelling behind. Spottiswoode concludes that Stoddard’s team has not shown natural selection to play a causative role, and except in a “satisfyingly general” way (i.e., a storytelling way), has really explained very little at all:Stoddard et al. conclude that variation in egg shape at a broad scale is best explained by variation in the need to fly. But although satisfyingly general, this discovery will be far from the final word. A bird’s egg was famously described by abolitionist Thomas Wentworth Higginson as “the most perfect thing in the universe” [3/09/17], but this apparent perfection is most likely the sum of multiple ecological, structural, and developmental compromises. It remains unclear why egg shapes tend toward being spherical in the absence of strong selection for powered flight. Do asymmetry and ellipticity carry costs, such as making an egg easier to break into or harder to break out of? And why has natural selection solved the streamlining problem with elongate and symmetric eggs in some species, and elongate and asymmetric eggs in others—that is, what best explains the variation along the x axis of the figure? Did elongate eggs repeatedly evolve in concert with narrower pelvises, and do their shell membranes vary in thickness and composition in the way that Stoddard et al.‘s model predicts? Their paper opens up a rich seam for researchers to explore.The authors end with nothing left but futureware , in hope that all the king’s horses and all the king’s men can pick up the pieces and build a better evolutionary story.Our macroevolutionary analyses suggest that birds adapted for high-powered flight may maximize egg size by increasing egg asymmetry and/or ellipticity, while maintaining a streamlined body plan. Moving forward, it will be important to determine how the developmental process of egg shaping is coupled, in terms of physiology and genetics, with evolutionary constraints associated with flight strength and efficiency.The very thing they promised to explain—egg shape by natural selection (‘selection pressure’)—they now say has to be be explained in the future—egg shaping by natural selection (‘evolutionary constraints’). If natural selection theory has this much trouble with something as simple as egg shape, how can it explain flight itself, where multiple adaptations must appear simultaneously to keep the bird airborne? (See the Illustra film, Flight: The Genius of Birds.)Exercise: Here’s another paper in PNAS that purports to show how natural selection explains symbiotic relationships. It looks very impressive, with lots of math and jargon. But does it really succeed in proving the explanatory power of Darwinian theory? Or is it more like the glitzy ballroom on the Titanic hiding a flawed engine room unable to sustain impact by the iceberg of pointed questions? Look for evidence of high PCI (perhapsimaybecouldness index), exceptions to rules, storytelling, speculation, and fudging of parameters to obtain desired conclusions.Recommended Resource: (Visited 649 times, 1 visits today)FacebookTwitterPinterestSave分享0last_img read more

Opinion: ‘It’s our turn to move South Africa forward’

first_imgThe freedom we now enjoy and celebrate was achieved through the selfless sacrifice of patriots who were prepared to pay the ultimate price, says the GCIS’ acting director-general Donald Liphoko. (Image: Shamin Chibba)By Donald Liphoko, acting director-general of GCISOn Freedom Day millions of South Africans will celebrate the day that marks the occasion of our first democratic elections in 1994 and gave birth to our freedom and constitutional democracy.Some will choose to spend the day at home surrounded by family and friends, others may gather at the national Freedom Day celebrations in Manguzi, Umhlabuyalingana Municipality, KwaZulu-Natal, which will be led by President Jacob Zuma. There are also those who may choose to use the national Freedom Day celebrations as a platform to raise their concerns.Whatever South Africans choose they will be free to do so. Our Constitution, our democracy, and our freedom have ensured that all people across our land are free to celebrate in the manner of their choosing.At face value, this seems utterly obvious, but we must never forget that before 1994, what now seems so utterly normal was denied to the majority of our fellow countrymen and women.The freedom we now enjoy and celebrate was achieved through the selfless sacrifice of patriots who were prepared to pay the ultimate price. They lived and died for the dream of a free and democratic South Africa that would be truly united, non-racial, non-sexist and prosperous. A country where everyone no matter their present circumstances would be free to strive for a better and more prosperous tomorrow.Since 1994 our country, and successive democratic administrations have worked to make this vision a reality. South Africa is undeniably a better place today than it was at the birth of our freedom, but much work still remains to undo the apartheid legacy of poverty, inequality and unemployment.The administration of President Jacob Zuma has continued this work since 2009. As a caring government, we continue to push for a society that is more equal, both socially and economically. Sadly, some have sought to push back against this vision by advocating that the status quo should remain in place.Such a call is both untenable and deeply worrying. We cannot and will not allow the continued existence of two parallel countries, and economies. It cannot be that our freedom dividend should only benefit some in our society, while the majority remain trapped in an existence of poverty, inequality and unemployment.Therefore government will continue its push for meaningful and inclusive economic transformation, that not only benefits some but all in our country. Our priority is to ensure greater participation in the economy by historically disadvantaged communities.We have already begun to implement this through our Medium-Term Strategic Framework 2014 to 2019. It sets out 14 outcomes around which we will mobilise all sectors of our society and it aims to ensure more equitable growth of the economy.These interventions should be seen as part of government’s long-term economic plan as guided by the National Development Plan, and immediate interventions such as the Nine-Point Plan, and Operation Phakisa.We are aware that many would argue that our immediate challenges cannot be resolved by the NDP, which is a long-term plan. However, the NDP is more than just a plan; it is the overarching vision for South Africa. Therefore it includes all key policy instruments aimed at growing the economy and creating jobs.These include the New Growth Path, which sets the trajectory of economic development; the National Infrastructure Plan, which guides the roll-out of infrastructure to improve people’s lives and enable economic growth; and the Industrial Policy Action Plan, which focuses on promoting investment and competitiveness in leading sectors and industries.Together these interventions are a potent driver for inclusive and far-reaching economic growth. However, our nation faces strong headwinds in the form of a slowing economy and global economic weakness. Therefore we need all South African onboard to tackle both our economic and social challenges.Let us, therefore, move away from the rhetoric and grandstanding. It is a luxury our country cannot afford. We must ensure that our dialogues are fair, less acrimonious and more constructive.As a caring government we will continue to lead the way by providing hope to all South Africans. Our social assistance programmes have lifted millions of people out of despair, and have planted the seeds of hope.The structural changes we are implementing will spur economic growth and ultimately lead to an economy and society that is more equitable. However, we cannot do it alone and need every sector of society to partner with us in this endeavour.Many South African companies have reaped the fruits of our freedom and have over the years have grown into strong multi-national corporations.As pillars in industry, we encourage them to use their success to move the country forward as we create the nation we all envisioned at the start of democracy. When South Africa benefits we all stand to benefit. Equally, we call on society to put aside narrow self-interest. Together we can build the country of our dreams; a nation which is prosperous, equitable and provides space for everyone to shine.The patriots who lived and died for our freedom have paved the way for this future, now it’s our turn to move South Africa forward.last_img read more

Is speech recognition software having a renaissance?

first_imgFollow the Puck Related Posts Tags:#featured#IBM#Internet of thngs#IoT#Microsoft#Omilia#top#voice recognition Nicolas De Kouchkovsky is the founder and principal at CaCube Consulting. He is an Advisor and Consultant to B2B software companies, helping them grow. Nicolas covers all aspects of marketing and market development, working on a project basis or as a VP of Marketing on demand. He spent over 25 years in the Cloud and Software industry as a product and marketing executive.Nicolas as extensive experience with Enterprise Software markets and is a recognized expert in customer facing technologies including Customer Service, Contact Centers, Sales, E-commerce, and Analytics.Nicolas held numerous executive roles at Genesys. As head of Product Management, he transformed the company from Computer Telephony Integration (CTI) middleware to a Software Application provider. As Chief Marketing Officer, he drove the company expansion in the broader multi-channel Contact Center market. Before joining Genesys, Nicolas held several senior positions at Alcatel-Lucent where he most notably established and developed the Call Center business. Prior, he was Chief Technology Officer at Cirel, a startup that pioneered multi-protocol gateways and ran a Software Integration practice at Digital Equipment (now Hewlett Packard). Nicolas De Kouchkovsky Small Business Cybersecurity Threats and How to… Why IoT Apps are Eating Device Interfaces Internet of Things Makes it Easier to Steal You… The past months have witnessed breakthrough announcements from Microsoft, IBM, and Google, all hitting new marks in speech recognition accuracy; they claim that the error rate has reached 5.1 percent — the word error rate of humans.Still, that doesn’t seem particularly accurate — the last time I spoke to a machine, I didn’t get the feeling that the recognition was nearly that good. Let’s review the next generation of speech technologies, how they are enabling new analytics, and the growing role of these insights for businesses to see whether the companies’ claims are accurate.Some history of speech recognitionIn early 2000, speech recognition reached 80 percent accuracy. In the enterprise space, it triggered adoption for Interactive Voice Response (IVR), which was initially implemented to remove the complications involved in customer service problems.But speech applications were very dependent on vocabularies and languages. They required a sophisticated set-up by highly specialized system integrators, and each major language had its speech recognition startup. It was only in 2005, when Nuance snapped up 15 companies, that the space was consolidated.See also: Amazon makes it cheaper for developers to use Alexa voiceAside from speech usage for IVR, a second use case emerged for Quality Management (QM). Customer service organizations use quality management applications to listen to call center calls and rate them. The process used to be tedious, limited to a small sample of calls, and like looking for a needle in a haystack. With speech recognition, it became possible to automate parts of the process. Workforce optimization leaders NICE and Verint developed or bought ways into speech analytics, followed by Contact Center Infrastructure players like Avaya or Genesys.These developments remained limited. IVR speech enablement has failed to transform the customer experience, and voice self-service experiences continue to be rated poorly. Speech for QM is often confined to compliance or script adherence verifications. At the beginning of the 2010s, it seemed that speech technology had stalled.The machine learning transformationWhile speech for customer service was developing, Amazon, Apple, Google, IBM, and Microsoft continued investing in research and development of speech technologies, driven by the vision it would eventually become critical for user interaction with machines.Apple broke into the market with the introduction of Siri, which used machine learning to transform speech recognition. Artificial intelligence removed many of speech technology’s complications and intricacies, as well as the need to re-engineer the stack for new languages or new vocabulary sets.Today, most digital disrupters, most notably China “Big Three,” Alibaba, Baidu, and Tencent, are building their speech stack. Because generic machine learning engines can be used, barriers to entry have been lowered dramatically. Open source options, like CMUSphinx, HTK, Julius, Kaldi, and Simon, are also widely available.Disrupting the customer service spaceThe AI breakthrough has paved the way for new entrants. Companies like iFLYTEK or Speechmatics are aggressively addressing the issues of usability, accuracy, and deployability, in particular beyond the dominant languages.For customer service, the battle is now shifting to the other half of the equation, Natural Language Processing (NLP) and Natural Language Understanding (NLU).Yactraq is applying its patented technology to democratize audio mining. It is finding that, by democratizing the technology for businesses, it can enable businesses to innovate besides compliance and adherence, helping discover best practices in customer interaction.Deep Learning has been powering its speech stack since 2013. It now sees NLU as the next frontier, as it can understand more than one command from different, simultaneous speakers, and prioritize them. After targeting automation and assistance for call centers, it is expanding in other industries and use cases. This industry focus is critical to finding solutions.Omilia is another intriguing story. Originally formed as an IVR system integrator, in 2007, it started developing its own speech technology with the vision to leapfrog IVR-directed dialogs and offer natural conversations. Omilia was able to leverage deep learning to assemble its stack; its technology bolstered an impressive 59 percent reduction in IVR abandonment and a double-digit increase in self-service completion at Royal Bank of Canada.Sales communication leading the way?Inside selling is on the rise, and as a result, sales communication has become an active and innovative space. A growing number of sales interactions are taking place over the phone, and sales executives are concerned about becoming blind to these is a pioneer of the sales intelligence space. Cultivating a solutions approach, it has assembled a vertically-integrated stack that provides a broad range of indicators for assessing the effectiveness of conversations and correlates sales process elements to actual outcomes. It uses homegrown speech recognition, tuned and modeled for sales conversations. The company is baking its know-how in a three-step “onboarding” process, recording all conversations to uncover insights in a matter of days. These insights are then used to create dashboards tracking performance drivers, which can eventually be monitored in realtime and used to drive changes on the front was born from one of its founders experiencing building fast growing sales teams. The founder got frustrated with inaccurate, undeveloped, superficial tools for measuring performance. He reviewed existing tools and found them too complex and ill-suited for B2B sales, which have long, unscripted conversations that can involve more than two participants. focuses on conversation intelligence by uncovering topics and recognizing performance patterns. Founded recently, in August 2015, assembled its first solution in record time.The sales technology space, though recent, is incredibly dynamic: in only a few years, it evolved beyond coaching and performance management to provide broader prospect and customer insights. Sales technology is poised to become a key element of Voice of the Customer (VoC) programs.Across the three market landscapes —Inside Sales, Interaction Management, and Intelligent Assistance and Bots — I am maintaining with VB Profiles, I have identified over 30 players:Artificial intelligence is transforming the speech industry. Within a given domain or use case, voice recognition technology is very accurate. Usability still has not been perfected, and NLP and NLU have yet to be implemented, but speech technology has already become mature enough to stimulate the creation of new applications and markets — more startups and innovations should be on the way.last_img read more