Camellias and the weevils that attack their seeds seem locked in conflict. The thicker a camellia grows its protective woody covering around its seeds, the longer the feeding tube on some weevil to break through and devour. John R. Thompson talked about such “coevolutionary arms races” in Current Biology1 and asked whether such wars can go on forever, leading to increased exaggeration of traits. The answer is, apparently, there are limits. Traits vary in a mosaic pattern across populations. Not all camellias are infested by beetles with the longest boring tools. As with any war, there are hotspots and coldspots. The dynamics of arms races seem to buffer both species against extremes.Collectively, these studies suggest that coevolution is a pervasive process that continually reshapes interspecific interactions across broad geographic areas. And that has important implications for our understanding of the role of coevolution in fields ranging from epidemiology to conservation biology. Many diseases, for example malaria, vary geographically both in parasite virulence and host resistance, potentially creating regions of coevolutionary hotspots and coldspots. The spread of introduced species seems be creating new geographic mosaics of coevolution as some species become invasive and coevolve with native species in different ways in different regions or drive rapid evolution in native species, sometimes in less than a hundred years or so. The results for Japanese camellia and camellia weevils reinforce the developing view that interactions coevolve as a geographic mosaic across landscapes, and it is often difficult for one partner to get ahead of the other (or others) everywhere. (Emphasis added.)1John R. Thompson, “Coevolution: The Geographic Mosaic of Coevolutionary Arms Races,” Current Biology, Volume 15, Issue 24, 24 December 2005, pages R992-R994, doi:10.1016/j.cub.2005.11.046.This appears to provide more slippage on the evolutionary treadmill (see 03/17/2003 entry). Though the word “evolution” is involved, don’t be confused; this has nothing to do with macroevolution, like bacteria evolving into people. Coevolution leads to exaggerated traits between two interacting species, like the beaks of hummingbirds and the flowers they pollinate. As with all other observed forms of microevolution, including Darwin’s famous finches, it involves the modification of existing traits – not the origin of new ones. Notice how quickly changes can result; Thompson referred to rapid “evolution” in native species in less than 100 years after an intruder was introduced. Young-earth creationists could use such concepts to explain the rapid diversification of varieties and species within created kinds, and there would be nothing Thompson or the Darwinists could do to prove them wrong. Studies like this do not establish that coevolution can be extrapolated endlessly into macroevolution. In fact, the quote above seems to indicate otherwise: there are limits to the amount of change in the “coevolutionary arms race.” World War II did not produce Superman. (Visited 65 times, 1 visits today)FacebookTwitterPinterestSave分享0
Related Posts It’s easy to fall into the trap of thinking of the app economy as a fully developed and mature space. And while it’s not the wild wild West that it was two years ago, the economy is still rapidly evolving – and we’re about to see some significant changes in 2011. 1. The Virtual Good is God – it’s all about in-app purchasingDoes it seem like everyone and their mother are talking about virtual goods? That’s because everyone is. And everyone’s mother just spent $200 buying virtual cows for her virtual farm. The virtual currency economy is big and growing – and it’s no joke for gaming publishers looking to monetize. Inside Virtual Goods recently published a report predicting that the virtual goods market in the U.S. alone will hit $2.1 billion in revenues this year.Monetization through virtual goods made a splash in 2010, but in 2011 we’ll see the economy grow into a real beast to be reckoned with. This year more iPhone and Android games will move from paid or subscription-based apps to a combination of in-app purchasing and advertising to monetize. Guest author Michael Chang is co-founder and the CEO of Greystripe. He has worked as an associate at Incubic Venture Capital and as an engineer and product manager with SAN pioneer Gadzoox Networks. He has a MBA from Duke University’s Fuqua School of Business and a BS from Carnegie Mellon.2. Mobile ads are about to transform – the formats and placements within apps are going to changeWhen mobile ads first hit the market, the online format was simply slapped onto the smartphone. Since the beginning, standard banner ads have been king – placed haphazardly on every screen of an app and each page of the mobile Web. This year will be the year advertisers start to pay as much attention to where and how an ad is placed as they do to the number of impressions and clicks. We’re going to start seeing more and more large, engaging ads delivered as interstitials – placed at natural transition points in content. The actual ads are evolving too. Rich media will become common. Video ads will also grow dramatically, which will come as no surprise to any Angry Bird-er who experienced video ads this holiday season.3. Regional and local ads will become commonplace – but hyperlocal ads will wait until 2012Local was the mobile buzzword of 2010 – and it’s not going away any time soon. Throughout the year, local and regional ads are going to be popping up more frequently. BIA/Kelsey predicts location-targeted ads will grow from $400 million in 2010 to over $2 billion by 2014. Scale is driving better opportunities for targeting, and more advertisers are taking advantage. But even though the climate is ripe for local, you shouldn’t expect an onslaught of hyperlocal ads. Yes, you’ll start seeing more ads for the Best Buy near you. But you won’t be overwhelmed with ads for the pizza place downstairs quite yet.4. An Android application store will enhance payment and discovery. (It better, if Android wants to win the competition for developers.)Last year was the year for Android – Google’s Android OS overtook iPhone in the total number of subscribers. But with the iPhone coming to Verizon, Android is going to have to step up its game if it wants to stay on top. In particular, Android’s marketplace has proven to be a key limitation. Apple’s App Store, while hardly perfect, is far superior to Android’s for finding and purchasing new apps. Android needs to figure out a way to organize its apps and simplify the checkout process. Someone will figure it out in 2011. Maybe it will be Google who has announced plans for upgrades. Maybe it will be a third party like Amazon.5. The wild cards: Emerging platforms, cross-platform HTML5 apps, non-Apple tablets and interactive TV A few potential app economy game changers need to be watched this year. Windows and Blackberry will make a strong push in 2011 for market share of high-end smartphones. This could increase fragmentation of the mobile app economy but should also contribute to the shift toward cross-platform HTML5 mobile websites that look and feel like native apps. The introduction of iPad alternatives will be an indication of how big the tablet market can be. Google and Apple’s TV products will test if the mainstream is ready for interactive TV. It’s clear that we’re entering an exciting time.Disclosure: the author is the CEO of a mobile advertising network.Photo by Jorge Quinteros Role of Mobile App Analytics In-App Engagement What it Takes to Build a Highly Secure FinTech … guest author 1 Tags:#apps#mobile#Trends Why IoT Apps are Eating Device Interfaces The Rise and Rise of Mobile Payment Technology
In her new role as UNHCR Special Envoy, Angelina Jolie has made five trips to visit refugees so far this year. She travelled to Jordan, Lebanon and Turkey in September 2012 to meet some of the tens of thousands of Syrians who have fled conflict in their homeland and sought shelter in neighboring countries.Jolie wrapped up her Middle East visit in Iraq, where she met Syrian refugees in the north as well as internally displaced Iraqis and refugee returnees to Baghdad.The UNHCR has posted a set of unpublished photos that were taken during her visit to the Middle East and show her meeting with Syrian and Iraqi refugees. The photos can be found here.