| Basics: Surviving by Disguising: Nature’s Game of Charades There are many cases of mimicry in nature, which can be the sincerest form of flattery, the severest form of battery, or the weirdest survival strategy. feeds.nytimes.com |
Vital Signs: Perceptions: Mistrust Seen as Barrier to Blood Donation Among African-Americans, mistrust of hospitals is high, a new study suggests, offering a possible explanation for their historically low rate of blood donation. feeds.nytimes.com |
Letters: A Specious Species? (3 Letters) Letters to the editor. feeds.nytimes.com |
Mystery Bird: Cooper's Hawk, Accipiter cooperii At first glance, this bird looks impossible to identify from this particular image, but there are some important clues that give it awayCooper's hawk, Accipiter cooperii, photographed at the 14th annual hawk watch at Smith Point, Gulf Coast Bird Observatory, Chambers County, Texas, USA.Image: Joseph Kennedy, 30 September 2010 [with binoculars].Nikon D200, Kowa 883 telescope with TSN-PZ camera eyepiece 1/750s f/8.0 at 1000.0mm iso400Question: I'm not sure whether most of you can identify this species, but there are a couple clues in this image that should prove helpful for those who know what to look for -- and yes, you are invited to "blurt out" this species' ID whether you are a beginner or an expert (but you must say which field marks you used to settle upon your identification). Response: This bird is a Cooper's hawk, Accipiter cooperii -- a juvenile, as revealed by its pale nape. This species is often confounded with the smaller sharp-shinned hawk, especially since large female "sharpies" can be nearly the same size as small male "coops." But there are several clues in this image that help us determine this bird's identity. First, it has a rounded tail, which is characteristic of Cooper's hawks (sharp-shinned hawks' tail feathers are all the same length, which gives it a blunt, squared-off appearance). Second, the just-visible right leg provides a hint: Sharp-shinned hawks have very thin legs while Cooper's hawks' legs are stouter. But this field mark requires some experience with looking at these species since it is sometimes difficult to decide if the bird's legs are thick or not. If you have bird images, video or mp3 files that you'd like to share with a large and appreciate audience, feel free to email them to me for consideration.GrrlScientistguardian.co.uk © Guardian News & Media Limited 2010 | Use of this content is subject to our Terms & Conditions | More Feeds guardian.co.uk |
Dino death made mammals 'go nuts' After the dinosaurs were wiped out, mammals went from scurrying "vermin" to giant beasts in just 25 million years, a study shows. bbc.co.uk |