Readers’ wildlife photos

Why Evolution Is True

Stephen Barnard continues the saga of the bald eagle nest that was built in the middle of a great blue heron rookery. Apparently the eagle chicks have hatched, but haven’t been seen yet.

This is the male eagle guarding nest area, perched on an abandoned heron nest. These birds have sexually dimorphic behaviors. I haven’t seen the female off the nest in many weeks. She’s incubated eggs in some very cold weather. The male is active, fishing for the female and now for the eaglets, and when he’s not fishing (most of the time) he’s on guard for intruders. The herons have given up on the rookery. That’s sad, but life goes on. They’ve moved to build another rookery across a field, but they probably won’t have a good breeding season. Someday the eagle nest will blow down — it’s not sited well — and they’ll move and the herons will 

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Pterosaurs take Manhattan

Why Evolution Is True

by Greg Mayer

Last weekend, a new exhibit opened at the American Museum of Natural History in New York: “Pterosaurs: Flight in the Age of Dinosaurs“. The New York Times had a piece on the making of the exhibit last week, and today their museum critic, Edward Rothstein, weighs in with his take on the pterosaurs. We’ve had occasion to favorably note Rothstien’s reviews previously here at WEIT, and his conclusion is that the exhibit is well worth seeing.


He writes:

The exhibition is unusually compelling, given its directness and simplicity. In one sense, pterosaurs are quite familiar: Any image of the dinosaur age shows them ruling the skies. But as you work your way through this exhibition, they become confoundingly strange. Walking on wings! A fourth finger for flying! Crests larger than heads!

His review also considers how it is we come to know…

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حملة نهوض

حملة نهوض من جل مصر هى حملة شبابية اسكندرانية لتوعية الاهالى بطريقة الاختيار الانسب والافضل للمرحلة حتى لا نرجع ونبكى على اللبن المسكوب 

اتمنى من اهل الاسكندرية خاصة واهل مصر عامة حسن الاختيار لمن يمسلهم فى انتخابات الرائسة وانتخابات مجلس الشعب وان يكون الاختيار على اساس الانسب 

الجهاز الهضمى

جهاز الهضم قناة طويلة و متعرجة تبدأ بالفم و تنتهي بفتحة الشرج[1]. وهو الجهاز المسؤول عن هضم الأغذية حيث يحول جزيئات الغذاء المعقدة و الكبيرة إلى جزيئات أصغر قابلة للامتصاص أي تستطيع النفاذ [2]عبر الأغشية الخلوية.
و تتم هذه العملية بواسطة تأثيرات ميكانيكية تحدث بفعل العضلات والأسنان وتأثيرات كيميائية تحفزها الأنزيمات.

[1] فتحة الشرج : فتحة موجودة في نهاية المعي المستقيم.

[2] النفاذ: العبور.