| The more extensive but misleading claim of Peter and Rosemary Grant is that “selection oscillates in a direction.” Even if this doubtful assertion were true, it would ultimately be irrelevant for the origin of primary species and higher systematic categories. A sieve (natural selection), after all, cannot create new grains. Show
Darwin thought that evolution took place over hundreds or thousands of years and was impossible to witness in a human lifetime. Peter and Rosemary Grant have seen evolution happen over the course of just two years. The Grants study the evolution of Darwin's finches on the Galapagos Islands. The birds have been named for Darwin, in part, because he later theorized that the 13 distinct species were all descendants of a common ancestor. Each species eats a different type of food and has unique characteristics developed through evolution. For example, the cactus finch has a long beak that reaches into blossoms, the ground finch has a short beak adapted for eating seeds buried under the soil, and the tree finch has a parrot-shaped beak suited for stripping bark to find insects. The Grants have focused their research on the medium ground finch, Geospiza fortis, on the small island of Daphne Major. Daphne Major serves as an ideal site for research because the finches have few predators or competitors. (The only other finch on the island is the cactus finch.) The major factor influencing survival of the medium ground finch is the weather, and thus the availability of food. The medium ground finch has a stubby beak and eats mostly seeds. Medium ground finches are variable in size and shape, which makes them a good subject for a study of evolution. The first event that the Grants saw affect the food supply was a drought that occurred in 1977. For 551 days the islands received no rain. Plants withered and finches grew hungry. The tiny seeds the medium ground finches were accustomed to eating grew scarce. Medium ground finches with larger beaks could take advantage of alternate food sources because they could crack open larger seeds. The smaller-beaked birds couldn't do this, so they died of starvation. In 1978 the Grants returned to Daphne Major to document the effect of the drought on the next generation of medium ground finches. They measured the offspring and compared their beak size to that of the previous (pre-drought) generations. They found the offsprings' beaks to be 3 to 4% larger than their grandparents'. The Grants had documented natural selection in action. While beak size is clearly related to feeding strategies, it is also related to reproduction. Female finches tend to mate with males that have the same size beaks. These factors together can add to the development of new species. The Grants return each year to Daphne Major to observe and measure finches. They have been collecting data on the finches for over 25 years and have witnessed natural selection operating in different ways under different circumstances. More offspring are produced than can survive because of limited resources such as food and nesting sites. Supported by: Recent key developments in the exploration of kagome materials are reviewed, including fundamental concepts of a kagome lattice, realizations of Chern and Weyl topological magnetism, flat-band many-body correlations, and unconventional charge-density waves and superconductivity. Microsoft and Sony are both battling behind the scenes over the Activision Blizzard deal, and Microsoft is no longer pulling its punches with regulatorsBy Tom Warren / @tomwarren Oct 12, 2022, 6:23 PM UTC| Share this story
Illustration by Alex Castro / The Verge Microsoft isn’t happy with Sony and the UK’s Competition and Markets Authority. The UK regulator signaled an in-depth review of Microsoft’s $68.7 billion deal to acquire Activision Blizzard last month, and the CMA has now published its full 76-page report (PDF) on its findings. The CMA says it has concerns that Microsoft’s Activision Blizzard deal could lessen competition in game consoles, subscriptions, and cloud gaming, but Microsoft thinks the regulator has simply been listening to Sony’s lawyers too much. Microsoft pleaded for its deal on the day of the Phase 2 decision last month, but now the gloves are well and truly off. Microsoft describes the CMA’s concerns as “misplaced” and says that the regulator “adopts Sony’s complaints without considering the potential harm to consumers” and “incorrectly relies on self-serving statements by Sony which significantly exaggerate the importance of Call of Duty.” Microsoft even accuses the CMA of adopting “Sony’s complaints without the appropriate level of critical review,” suggesting that the regulator is simply just listening too much to what Sony has to say. At the heart of all the back and forth is access to Call of Duty and concerns around the future of game subscriptions. “The CMA recognizes that ABK’s newest games are not currently available on any subscription service on the day of release but considers that this may change as subscription services continue to grow,” says the UK regulator. “After the Merger, Microsoft would gain control of this important input and could use it to harm the competitiveness of its rivals.” Microsoft’s full response to the CMA, seen by The Verge, also includes parts where the company tries to, comically, make it look like it somehow sucks at gaming and it can’t compete. Microsoft says Xbox “is in last place in console” and “seventh place in PC” and “nowhere in mobile game distribution globally,” and Microsoft argues it has no reason to harm or degrade rival cloud gaming services as it wants to “encourage the major shift in consumer behavior required for cloud gaming to succeed.” Microsoft might well be in last place in console sales during the previous generation, but it’s certainly investing billions of dollars to ensure any future Xbox sales aren’t less than half of the PlayStation and that its Xbox Game Pass bet pays off. Sony and Microsoft have also been battling it out over Call of Duty, and the CMA recognizes this by revealing it’s concerned about Sony’s future revenues related to Call of Duty. “PlayStation currently has a larger share of the console gaming market than Xbox, but the CMA considers that Call of Duty is sufficiently important that losing access to it (or losing access on competitive terms) could significantly impact Sony’s revenues and user base.”
Call of Duty is at the center of Sony and Microsoft’s battles.Image: Activision Sony has shown how significant Call of Duty is after it labeled Microsoft’s offer to keep Call of Duty on PlayStation “inadequate on many levels.” The Verge revealed last month that Microsoft Gaming CEO and Xbox chief Phil Spencer made a written commitment to PlayStation head Jim Ryan earlier this year to keep Call of Duty on PlayStation for “several more years” beyond the existing marketing deal Sony has with Activision. “After almost 20 years of Call of Duty on PlayStation, their proposal was inadequate on many levels and failed to take account of the impact on our gamers,” said PlayStation head Jim Ryan in response. Now Microsoft says keeping Call of Duty on PlayStation is a “commercial imperative for the Xbox business and the economics of the transaction.” Microsoft says it would put revenue at risk if it pulled Call of Duty from PlayStation and that “Microsoft has been clear that it is counting on revenues from the distribution of Activision Blizzard games on Sony PlayStation.” Microsoft also accuses Sony of not welcoming competition from Xbox Game Pass and that Sony has decided to block Game Pass on PlayStation. “This increased competition has not been welcomed by the market leader Sony, which has elected to protect its revenues from sales of newly released games, rather than offer gamers the choice of accessing them via its subscription, PlayStation Plus.” This comes just months after Microsoft claimed, in legal filings, that Sony pays for “blocking rights” to keep games off Xbox Game Pass. If the UK battles are anything to go by, this acquisition could get messy as Microsoft and Sony battle it out behind the scenes to sway regulators. Microsoft even has a dedicated website to highlight its arguments as it seeks to convince regulators that its giant deal isn’t a bad one for gamers. We’re still months away from final regulator decisions, but get ready for this battle to continue to spill out onto the internet’s streets. Join the conversation Most Popular
Verge Deals/ Sign up for Verge Deals to get deals on products we've tested sent to your inbox daily. Email (required)Sign up By submitting your email, you agree to our Terms and Privacy Notice. This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply. How did the drought lead to an increase in beak size in the medium ground finch population?Why do you think the average beak depth of the birds increased? Because the drought reduced the number of seeds and finches with bigger beaks were able to eat the larger and harder seeds so more of them survived.
What was the effect of the 1977 drought on the medium ground finch?Recently they reported a change in the beak size of the medium ground finch on Daphne Major. In 1977 a drought reduced the number of small seeds available for the birds, forcing them to rely on larger seeds requiring considerable force to open.
What caused the decline of the finch population?1: Finches of Daphne Major: A drought on the Galápagos island of Daphne Major in 1977 reduced the number of small seeds available to finches, causing many of the small-beaked finches to die.
What percentage of the medium ground finches died due to the drought?Around 1,200 medium ground finches were alive at the beginning of the drought, but fewer than 200 survived, a loss of 85%. Most of the survivors were larger and had larger beaks.
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How might an extended period of drought influence the ground finch population
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