Birds call fowl on cuckoo’s antics

first_imgThe common cuckoo is what biologists call a brood parasite; it lays eggs in other birds’ nests, hoping the mothers won’t notice. Often they don’t, because cuckoo eggs have evolved to closely resemble those of their victims. And once the cuckoo hatches, the invader seizes the nest, pushing out all the other eggs. The parasitized birds, however, are fighting back. There’s an ongoing evolutionary arms race between the cuckoo and its most frequent victims, such as the brambling and the red-backed shrike. The parasitized birds are evolving unique egg “signatures,” markings that help the mother distinguish an authentic egg from an impostor. Though scientists have had ideas about how this arms race works, a study published this week in Nature Communications suggests that the egg war isn’t playing out the way we’d once thought. The conventional wisdom is that recognizable eggs must have three visual qualities: They should be highly similar to eggs holding their siblings; distinct from eggs laid by other mothers of the same species; and have complex, dense markings to make them more difficult to mimic. But when researchers analyzed hundreds of eggs from eight different parasitized species, they found a different story. Eggs didn’t necessarily need all three attributes to be distinguishable. For example, brambling parents were able to identify their eggs even though there was a lot of variation among sibling eggs and little difference between eggs from different mothers. The scientists also found that complex, dense egg markings could actually make it more difficult for mother birds to recognize their eggs. The insights suggest moderation may be a winning tactic in the egg war: Markings need to be visually dense enough to convey some information, yet not so dense that the egg becomes unrecognizable.last_img read more

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first_img Top Stories Through six games, Arizona is 3-3, and they have yet to win a game because of their quarterback. But they have lost games because of him. In the win over Detroit, Arizona got four field goals from Jay Feely, a blocked field goal on special teams by Justin Bethel and big plays by Andre Ellington and Tyrann Mathieu. In the win over Tampa Bay, the Cardinals overcame two Palmer interceptions and won behind two picks by Patrick Peterson, a fumble recovery by Matt Shaugnhessy and a defense that held the Buccaneers to 253 yards, including just 45 yards on 27 carries by Doug Martin. That, by the way, was the game head coach Bruce Arians called the Cardinals offense “putrid.” Against Carolina, the Cardinals overcame three more interceptions by Palmer and relied on a defense that had seven sacks and three interceptions to lead the way.At some point, Palmer has to win his teammates and fans over by winning a game for Arizona. He has to have a game in which he limits his mistakes and leads the Cardinals. He is more than capable of being the catalyst in some Cardinals wins. Right now, Arizona is 3-3 because of special teams and defense. The offense has yet to deliver, and that is on Palmer. It would be nice on a Big Red Monday to praise Palmer for leading the team to victory and not rip him for another lackluster performance. The 5: Takeaways from the Coyotes’ introduction of Alex Meruelo 0 Comments   Share   Grace expects Greinke trade to have emotional impact Derrick Hall satisfied with D-backs’ buying and selling Former Cardinals kicker Phil Dawson retires There is no denying that quarterback is the most important position on a football team. That is why Joe Flacco of the Ravens just got $120.6 million. It’s why Tony Romo just got $108 million. It’s why the Broncos doled out $96 million last year to Peyton Manning. To win consistently in this league, you need to have a good quarterback. In a league with so much parity, a quarterback will be directly responsible for many of a team’s wins. Such is not the case with the Arizona Cardinals, and Carson Palmer yet.last_img read more