الاسود المتشرده

هي الاسود التي وصلت الي سن البلوغ وطردت من زمرتهاوتبدء  بالبحث عن زمره اخري لكي تتزاوج مع اناثها وغالبا ما يتحد اكثر من ذكر لكي يفعلوا ذلك ولكن عليهم ان يواجهوا ذكر اي زمرة يرغبوا في السيطره عليها وان لم يكن الذكر موجود فالاناث هي التي تقوم بذلك وتكون شرسه جدا في حاله كان لديها صغار لانهم سيقتلونهم للتزاوج مع امهاتهم

السرعوف

‎‏

من مزايا السرعوف (فرس النبي) أنه يتغذى على الحشرات مما يجعله أفضل حارس للمزارع من هجوم الحشرات وخاصة الجراد، والسرعوف يهجم على أي حشرة تتحرك أمامه ينقض على الحشرات بالكلابتين القويتين ويسرع في التهامها فهو لا يتوقف عن الأكل، ويكون أكثر نشاطاً خلال فصل الصيف حيث تكثر الحشرات الضارة بالمزارع . وله اشكال لكم صور من اشكاله....

Vietnamese mossy frog

Vietnamese mossy frog (Theloderma corticale) - By living in environments that are tropical and humid, this little frog has evolved a camouflage mechanism (its skin) that allows it to almost fully conceal itself from potential predators and blend in with the surrounding mossy environment. When threatened, it curls up into a ball and plays dead.

An interesting fact:
"Frogs have no hard palate in their mouth. Instead of pushing food to the top of their mouth in order to swallow it, they will pull their eyes down into the roof their mouth to help force food down their throats."

ثيران البايسون

تعيش في واحد من اصعب المناخات علي الارض حيث البروده والثلج الكثيف وصعوبه المشي فيه
ولكنه يتغلب علي ذلك بفرائه الكثيف وبعض المزايا الجسديه التي اكتسبها علي مر القرون

The red deer

The red deer (Cervus elaphus) is one of the largest deer species. The red deer inhabits most of Europe, the Caucasus Mountains region, Asia Minor, Iran, parts of western Asia, and central Asia. It also inhabits the Atlas Mountains region between Morocco and Tunisia in northwestern Africa, being the only species of deer to inhabit Africa. Red deer have been introduced to other areas, including Australia, New Zealand and Argentina.

Male European red deer have a distinctive "roar"-like-sound (not to be confused with actual roars made by lions, panthers and the like) during the rut, which is an adaptation to forested environments, as opposed to male (American elk or wapiti) which "bugle" during the rut in adaptation to open environments. The male deer roars to keep his harem of females together. The females are initially attracted to those males that both roar most often and have the loudest roar call. Males also use the roar call when competing with other males for females during the rut, and along with other forms of posturing and antler fights, is a method used by the males to establish dominance. Roaring is most common during the early dawn and late evening, which is also when the crepuscular deer are most active in general.

Rockhopper Penguins.

These gregarious marine birds are among the world's smallest penguins, standing about 20 inches (50 centimeters) tall. They have blood-red eyes, a red-orange beak, and pink webbed feet. During annual breeding times, rockhoppers gather in vast, noisy colonies, often numbering in the hundreds of thousands, to construct burrows in the tall tussock grasses near shore. They return to the same breeding ground, and often to the same nest, each year, and usually seek out their previous year's mate. Rockhoppers ply the frigid waters of their range using strong, narrow, flipper-like wings for propulsion. They usually stick to the shallows, but are capable of diving up to 330 feet (100 meters) in pursuit of fish, crustaceans, squid, and krill.

Giant Anteater

The anteaters are more closely related to the sloths than they are to any other group of mammals. Their next closest relations are armadillos. Three genera are still living: the giant and the silky anteaters, and the northern and southern tamanduas, and several genera are extinct. The giant anteater can reach 7 feet (2.1 meters) long from the tip of its snout to the end of its tail
Anteaters are edentate animals—they have no teeth. But their long tongues are more than sufficient to lap up the 35,000 ants and termites they swallow whole each day.

 
The anteater uses its sharp claws to tear an opening into an anthill and put its long snout and efficient tongue to work. But it has to eat quickly, flicking its tongue up to 160 times per minute. Ants fight back with painful stings, so an anteater may spend only a minute feasting on each mound. Anteaters never destroy a nest, preferring to return and feed again in the future.
These animals find their quarry not by sight—theirs is poor—but by smell.Anteaters are found in Central and South America, where they prefer tropical forests and grasslands.

اسماك شقائق النعمان

تعيش تلك الاسماك داخل شقائق النعمان وهي لها انواع كثيره والغريب ان الشقاق تلسع كل الاسماك التي تقترب منها الا تلك السمكه فعلي الارجح هي تمتلك مضاد للسعاتها وبذلك تحتمي اسماك الشقاق من الاسماك المفترسه الاخري

علماء يكافحون لحفظ الحيوانات من الانقراض

في سبيل سعيهم لحماية الأنواع المهددة بالانقراض، درس العلماء آلاف المناطق لتحديد تلك التي لا غنى عنها من أجل استمرار بعض الأنواع، معتبرين أن سبيل حماية تلك الأنواع يكون بحماية بيئتها.
ولتحديد أهمية كل موقع فإن العلماء فحصوا بيانات تتعلق بـ173 ألف موقع محمي، و21 ألف و500 نوع من الكائنات، وكان العامل الحاسم هو الطريقة التي يساهم بها الموقع في استمرارية أنواع بعينها، مما يجعله مؤهلا ليكون محمية. 
وتوصل العلماء إلى أنه بالإجمال فإن 173 منطقة في34 بلدا تم تحديدها كأكثر المواقع أهمية لحماية الأنواع، ورغم أن كثيرا من تلك المواقع تضعها فعليا منظمة الأمم المتحدة للتربية والعلوم والثقافة (يونسكو) ضمن قائمة التراث العالمي، إلا أن أكثر من نصفها ليست كذلك.
وتتضمن قائمة تلك المواقع الحديقة الوطنية الطبيعية "سييرا نيفادا دي سانتا مارتا" في كولومبيا، وهي موطن لأنواع مستوطنة ومهددة بالانقراض. إضافة إلى أماكن مثل محميات غابات "بارامو أوراو" الوطنية، والتي يقول عنها الرئيس التنفيذي لمنظمة "رينفورست ترست" الأميركية لحماية البيئة بول سالمان "إنها غير موجودة كموقع محمي إلا بالاسم فقط".
ويضيف سالمان بأنه "بينما من المنتظر أن تكون المواقع المحمية -التي تشكل 13% من مساحة الأراضي في العالم- محمية كما يقترح اسمها، لكن لأسباب عديدة فإن الحالة ليست كذلك".
وتبني هذه الدراسة -التي نشرت في مجلة "ساينس- على دراسات سابقة ألقت الضوء على أهمية زيادة أعداد الأماكن المحمية، لكنها من ناحية أخرى تركز على تحسين جهود إدارة الأماكن المحمية حاليا.
وتفصل الدارسة كيف أن العديد من خطط الإدارة المحلية تنطوي على التركيز على "الأنواع الكاريزمية" (مثل الدب القطبي) بطريقة يمكن أن تضر بالنظام البيئي ككل، مما دفع الباحثين للتوصية بضرورة أن تستهدف الحماية تلك الأنواع المهددة بالانقراض -بغض النظر عن صغرها وعدم جاذبتيها- التي تملك التزاما أكبر بحمايتها.
كما أوصى المؤلف الرئيسي للدراسة سوزيك مي ساوت بتضمين المواقع الأخرى غير المحمية في قائمة مواقع التراث العالمي، كي تحصل على حقها من الحماية التي يوفرها لها هذا التصنيف.

كلب الداروس

-الكلب "التبت" او "الدراوس"... كلب الداروس اي الكلب الضخم و هذا الكلب يعد من اكبر الكلاب من فصيلته هي يبلغ طوله حين يقف حوالي 31 بوصة و وزنه يتعدى الـ 140 رتل و هذا الكلب الملقب بـإسم "حارس المنزل" و هو يعد من الكلاب ذات حاسة الشم القوية جدا و من اشرسها حيث تم تجربة هذا الكلاب على مصارعة النمور و هو مالم يفعله اي فصيلة كلاب أخرى و متوسط سعره 582.000$ حول العالم. 

What is DNA?

DNA, or deoxyribonucleic acid, is the hereditary material in humans and almost all other organisms. Nearly every cell in a person’s body has the same DNA. Most DNA is located in the cell nucleus (where it is called nuclear DNA), but a small amount of DNA can also be found in the mitochondria (where it is called mitochondrial DNA or mtDNA).

The information in DNA is stored as a code made up of four chemical bases: adenine (A), guanine (G), cytosine (C), and thymine (T). Human DNA consists of about 3 billion bases, and more than 99 percent of those bases are the same in all people. The order, or sequence, of these bases determines the information available for building and maintaining an organism, similar to the way in which letters of the alphabet appear in a certain order to form words and sentences.

DNA bases pair up with each other, A with T and C with G, to form units called base pairs. Each base is also attached to a sugar molecule and a phosphate molecule. Together, a base, sugar, and phosphate are called a nucleotide. Nucleotides are arranged in two long strands that form a spiral called a double helix. The structure of the double helix is somewhat like a ladder, with the base pairs forming the ladder’s rungs and the sugar and phosphate molecules forming the vertical sidepieces of the ladder.

An important property of DNA is that it can replicate, or make copies of itself. Each strand of DNA in the double helix can serve as a pattern for duplicating the sequence of bases. This is critical when cells divide because each new cell needs to have an exact copy of the DNA presenin the old cell .

سمكه المارلين

يمكن لتلك السمه ان تسبح بسرعه 80 كيلو متر وتعتبر اسرع سمكه في العالم وتقتل باستخدام سيفها هذا انا عن طريق صدم الفريسه جانبيا او قطعها الي نصفيه او طعنها مباشره واختراقها وغالباما تصطاد اسماك السردين التي توجد في اسراب

علوم الحياة والأرض بالثانوي التأهيلي

http://yousvt.eb2a.com/index.html

كراسة أنشطة و دروس في مادة علوم الحياة و الارض 2 bac

http://diwan-svt.com/

افضل صور الحياه البريه

وما في الصوره هو افتراس الفقمه النمريه لبطريق وذلك في مياه القطب الشمالي

البقرة جنس من الحيوانات الثديية المجترة

البقرة جنس من الحيوانات الثديية المجترة. وجدت أصلا في الطبيعة سائبة بشكل وحشي، أستأنست منذ زمن طويل، واستخدمت لأغراض شتى من جر العربة والمحراث وتدوير الطاحونة والرحى وإدارة الساقية وللاستفادة من لحمها وحليبها وجلدها. البقرةُ اسم جنس البَقَرَةُ من الأَهلي والوحشي، يكون للمذكر والمؤنث ويقع على الذكر والأُنثى، وإِنما دخلته الهاء على أَنه واحد من جنس والجمع البَقَراتُ وصغيرهما يعرف بالعجل ويشبه حيوان الجاموس ولكنه يختلف في اللون والحجم. اشتق الاسم من بقر إذا شق لأنها تشق الأرض بالحراثة، من الحيوانات. البقرة مقدسة لدى الهندوس وللبقرة ذكر في الديانات السماوية فقصتها معروفة مع نبي الله موسى وبني إسرائيل وقد ذكرها الله في القرآن تفصيلا في سورة البقرة وهي أطول سور القرآن الكريم الحاوية على الأحكام. البقر حيوان شديد القوة كثير المنفعة خلقه الله ذلولا ولم يخلق له سلاحا شديدا كما للسباع لأنه في رعاية الإنسان، فالأنسان يدفع عنها ضرر عدوها. لأهمية الأبقار في توفير الحليب واللحوم والجلود فقد أخذت الدول عامة في تربيتها والاهتمام في تكاثرها بموجب نظم محسوبة ومحددة. هناك مرض لحق بالبقر في السنوات الأخيرة عرف بمرض جنون البقر وإن انحسر الآن. والبقر تتعدد ألوانه فمنه البني والأسود والأبيض والأصفر والمخلط من بين هذه الألوان.....أبقار الحليب هولستين بقرة جيرزي بقرة سويسرية بنية بقرة شامية بقرة عكشية وهي ثنائية الغرض (للحليب واللحم) أبقار اللحم أنغوس شاروليه (بالفرنسية: Charolais) هيرفورد الأكيتين الشقراء (بالفرنسية: Blonde d'Aquitaine)...

الشرشور

الطول يتراوح بين 14-16 سم و امتداد الجناحين يتراوح بين 24.5-28.5 سمو الوزن بين 18-29 جرام. يعيش الشرشور في الغابات المفتوحة و بالقرب من الحدائق و المتنزهات و الاراضي الزراعية. الشرشور يتغذى في الطبيعة على البذور و الثمار الصغيرة و الحشرات خاصة في موسم التزاوج و الانتاج و هو في تغذية الصغار يعتمد على الحشرات اكثر من البذور..

البرص ذو الذيل الورقي

يعيش البرص ذو الذيل الورقي في جزيرة مدغشقر يتواجد البرص ذو الذيل الورقي في الغابات يبلغ طوله ( 20,5 سم ) يتحرك بواسطة أربعة أطراف يسير عليه يتغذى البرص على الحشرات يتنفس بواسطة الرئـتين تضع أنثى بيضها في التربة تغطي الحراشيف جسم البرص مضغوط ذو عيون كبيرة بارزة ، ولونـه يشبـه لون قلف الأشجار ، وهو يرقد على فروع الأشجار أو جزع الشجرة ، و يستطيع أن يـغيـر شدة استضاءة ألوانـه ؛ فيصبح قاتماً في المساء والذيل يمكن أن ينثني إلى أعلى في اتجاه الظهر ويستخدمه كقدم خامسة للتعلق بالأغصان وهو ليلي النشاط ، ويقضي وقتاً بعد الطعام في تنظيف نفسه بلسانـه ، وحتى عيناه ا ينظفها...

بيت العنكبوت

و لا يقتصر بيت العنكبوت على أنه مأوى يسكن فيه ، بل هو في نفس الوقت مصيدة تقع في بعض حبائلها اللزجة الحشرات الطائرة مثل الذباب و غيرها .. لتكون فريسة يتغذى عليها . وتدل الدراسات المستفيضة للحشرات على أن بعضها له حياة اجتماعية ذات نظم و مبادئ و قوانين تلتزم بها في إعداد مساكنها و الحصول على أقواتها و الدفاع عن نفسها والتعاون فيما بينها بصورة تدهش العقول و ذلك بإلهام من خلقها الذي يجعلها تبدو و كأنها أمم لها كيان و نظام و عمران . قد راقب الباحثون أنواع مختلفة من العناكب فوجدوا أن لها قدرات فائقة في العمليات الإنشائية حين تشيد بيوتها و تنسج غزلها ن وكشف العلماء عن ثلاثة أزواج من المغازل الإنشائية حين تشيد بيوتها و تنسج غزلها ن وكشف العلماء عن ثلاثة أزواج من المغازل توجد في مؤخرة بطن العنكبوت تأتيها المادة الخام عن طريق سبع غدد في الأقل و أحياناً يصل عدد هذه الغدد في بعض أنواع العناكب إلى 600 ، و خيوط العنكبوت حريرية رفيعة جداً، حتى أن سمك شعرة واحدة من رأس الإنسان يزيد عن سمك خيط نسيج العنكبوت بحوالي 400 مرة . و إذا كانت هذه الخيوط تبدو ضعيفة واهية تمزقها هبة ريح ، إلا أن الدراسات أوضحت أنها على درجة عالية من المتانة و الشدة و المرونة . و من رحمة الله بعباده أن جعل العناكب ، و هي المخلوقات التي يتقزز منها الإنسان ، لا تخلو من فوائد عديدة ، فيه تلتهم الملايين من الحشرات الضارة بالنباتات أو الصحة ، أي أنها تعمل كمبيدات حشرية حية لدرجة أن أحد علماء الأحياء يؤكد أن نهاية الإنسان تصبح محققة على ظهر الأرض إذا ما تم القضاء على العناكب .

ابداع التصوير في البريه

مهنه ممتعه جدا حيث يعمل المصور علي التقاط لحظات سريعه من الطبيعه

صياد يسبح مع سرب

صياد يسبح مع سرب من الاسماك ويبدوا كانه واحد منهم

ضع ذبابه فوق جرحك..؟

اجـــــرى العلماء بحوث علمية على الذباب فوجدوا أن بعض يرقات الذباب تحتوي أجسادها على

بعض المواد التي تسمى بـ”بكتيريوفاج”و التي تساعد على سرعة إلتئام الجروح ولهذا

فقد يفيد وضع ذبابة فوق جرحك..لقد لاحظ بعض الأطباء أن الجروح التي وقف عليها بعض أنواع معينة من الذباب ونمت عليها بعض من يرقاته قد شفيت بصورة طيبة وعلى العكس فإن الجروح التي لم يقف عليها الذباب ولم تنمو عليها اليرقات قد تلوثت

Biologie cake

الحرباء او العظائه

تمتلك لسانا طويل جدا وسريع والسر هو ان لسانها لا يتكون من عضلات بل من انسجه مرنه تطلق قوتها دفعه واحده كما يفعل وتر القوس حيث يخرج طاقته مره واحده وبسرعه

art & bacteria

Instead of relying on toxic chemicals or harsh abrasives, an art restoration crew in Spain keeps its frescoes fresh by gently slathering a special kind of bacteria, one that is trained to survive by eating glue and salt residues, on the aging masterpieces.

Wired Science

RNA is best known to biology students as that stuff that helps translate genes into proteins. But the molecule also has a secret life outside the cell that scientists arejust beginning to understand. (Image: National Institutes of Health)just beginning to understand. (Image: National Institutes of Health)

الحياة البرية

شاهد: خنزير بري محاصر من قبل كلاب برية متوحشة .. ولامجال للنجاة
يرصد المقطع التالي صورة واقعية جداً عن الحياة البرية. خنزير برّي علق بين مجموعة من الكلاب البرية المتوحشة وتمساح ضخم… وبعد دقائق من التربص كانت الغلبة لشريعة الغاب. القوي يأكل الضعيف.

http://bit.ly/1azJ1WN

Space photo weekend edition: When the Fireworks Galaxy has a show, it doesn't use dinky gunpowder rockets. Instead, it explodes stars.

Inside the human hand

الحشرات الأحفوريّة

أستاذ العلوم البريّة والاحفوريّة Matthew Clapham بجامعة كاليفورنيا في Santa Cruz, والطالب Jered Karr: قاما بمُراكمة مجموعة من التفاصيل والمعطيات المتصلة بطول أجنحةالحشرات الأحفوريّة, قاموا بتحليل حجم الحشرات وصلته بمستويات الاوكسجين بالغلاف الجوي, خلال مئات ملايين الاعوام من تطور الحشرات.يؤكّد Clapham على:" حجم حشرات ما قبل التأريخ مرتبط بكميّة الاوكسجين الموجودة بالحقبة التي تقدّر بحوالي 200 مليون عام ". ويُضيف:" حيث ازداد الاوكسجين ولكن حجم الحشرة قل

طائر القرزبيل

يستخدم منقاره القوي والمتقاطع لفتح ثمار الصنوبر

النسر_الملك....

هذا الطائر يستغل تيارات الهواء أثناء الطيران في حمله كي تساعده على الطيران وتوفير طاقته خلال بحثه عن الطعام في الغابات أو الصحاري. ..

Today In History. What Happened This Day In History

1618		Sir Walter Raleigh is executed. After the death of Queen Elizabeth, Raleigh's enemies spread rumors that he was opposed the accession of King James.
1787		Mozart's opera Don Giovanni opens in Prague.
1814		The Demologos, the first steam-powered warship, launched in New York City.
1901		Leon Czolgosz is electrocuted for the assassination of US President William McKinley. Czolgosz, an anarchist, shot McKinley on September 6 during a public reception at the Temple of Music in Buffalo, N.Y. Despite early hopes of recovery, McKinley died September 14, in Buffalo, NY.
1927		Russian archaeologist Peter Kozloff apparently uncovers the tomb of Genghis Khan in the Gobi Desert, a claim still in dispute.
1929		Black Tuesday–the most catastrophic day in stock market history, the herald of the Great Depression. 16 million shares were sold at declining prices. By mid-November $30 billion of the $80 billion worth of stocks listed in September will have been wiped out.
1945		The first ball-point pen goes is sold by Gimbell's department store in New York for a price of $12.
1949		Alonzo G. Moron of the Virgin Islands becomes the first African-American president of Hampton Institute, Hampton, Virginia.
1952		French forces launch Operation Lorraine against Viet Minh supply bases in Indochina.
1964		Thieves steal a jewel collection–including the world's largest sapphire, the 565-carat "Star of India," and the 100-carat DeLong ruby–from the Museum of Natural History in New York. The thieves were caught and most of the jewels recovered.
1969		The U.S. Supreme Court orders immediate desegregation, superseding the previous "with all deliberate speed" ruling.
1969		First computer-to-computer link; the link is accomplished through ARPANET, forerunner of the Internet.
1972		Palestinian guerrillas kill an airport employee and hijack a plane, carrying 27 passengers, to Cuba. They force West Germany to release 3 terrorists who were involved in the Munich Massacre.
1983		More than 500,000 people protest in The Hague, The Netherlands, against cruise missiles.
1986		The last stretch of Britain's M25 motorway opens.
1998		South Africa's Truth and Reconciliation Commission reports condemns both sides on the Apartheid issue for committing atrocities.
1998		John Glenn, at age 77, becomes the oldest person to go into outer space. He is part of the crew of Space Shuttle Discovery, STS-95.
1998		The deadliest Atlantic hurricane on record up to that time, Hurricane Mitch, makes landfall in Honduras (in 2005 Hurricane Wilma surpassed it); nearly 11,000 people died and approximately the same number were missing.
2004		For the first time, Osama bin Laden admits direct responsibility for the Sept. 11, 2001, terrorist attacks in the US; his comments are part of a video broadcast by the Al Jazeera network.
2008		Delta and Northwest airlines merge, forming the world's largest airline.
2012		Hurricane Sandy devastates much of the East Coast of the US; nearly 300 die directly or indirectly from the storm.
Born on October 29
1882		Jean Giraudoux, French dramatist, novelist and diplomat, famous for his book Tiger at the Gates.
1891		Fanny Brice, comedian, singer and actress.
1897		Joseph G. Göbbels, German Nazi Propaganda Minister who committed suicide in Hitler's bunker.
1905		Henry Green, novelist (Living, Party Going).
1910		A. J. Ayer, English philosopher.
1921		Bill Maudlin, American cartoonist whose GI characters "Willie" and "Joe" appeared in Stars and Stripes newspapers during World War II.
1938		Ralph Bakshi, Palestinian-American director of live films and animated full-length films for adults including 1972's Fritz the Cat (first animated film to be rated X by the Motion Picture Association of America), Wizards (1977) and The Lord of the Rings (1978).
1943		Don Simpson, film producer, screenwriter, actor; (co-producer Flashdance, 1985; Top Gun, 1986).
1945		Melba Moore, disco and R&B singer, actress ("You Stepped into My Life," "Lean on Me").
1946		Peter Green, guitarist, songwriter, founder of the band Fleetwood Mac; regarded as one of the greatest guitarists of all time.
1947		Richard Dreyfuss, actor (American Graffiti, Jaws; won Academy Award for Best Actor for 1977's The Goodbye Girl).
1948		Kate Jackson, actress, director, producer (original Charlie's Angels TV series, Scarecrow and Mrs. King TV series).
1954		Lee Child, author; creator of the Jack Reacher novel series.
1958		David Remnick, journals, author, magazine editor (The New Yorker); won Pulitzer Prize forLenin's Tomb: The Last Days of the Soviet Empire (1994).
1971		Winona Ryder, actress, producer (Beetlejuice; Girl, Interrupted).

Beach Cave, Algarve, Portugal

my friend

"These images captured by nature photographer Lassi Rautiainen, show an unusual friendship between a lone wolf and a bear. The images show how the young brown bear and grey wolf would sit down to eat together and even enjoy views over the landscape for up to two-hours.

It’s never clear why these unusual pairings occur, but wild animals that get separated from their mothers too early, or that are cast out from the group (like this wolf, perhaps), sometimes take odd steps as they figure out how to survive on their own. A partner of any species might simply bring comfort, a sense of safety."

Rautiainen adds: "When I realised that no one had observed bears and wolves living near each other and becoming friends in Europe, I concentrated more and more on getting pictures to show what can happen in nature."

Holy cow! Dino flatulence may have changed ancient climate

Nev­er mind cows: di­no­saurs pass­ing gas could have re­leased enough cli­mate-altering meth­ane gas to warm the pre­hist­or­ic world, ac­cord­ing to newly pub­lished cal­cula­t­ions.

While many a stu­dent has snick­ered over the ob­serva­t­ion that flat­u­lat­ing live­stock con­trib­ute to the at­mos­pher­ic green­house gas­es blamed for glob­al warm­ing to­day, deal­ing with a hulk­ing ap­at­o­saur­us (a.k.a. bron­to­sau­rus) with in­di­ges­tion might have been no laugh­ing mat­ter.

The new re­search pub­lished in the May 8 is­sue of the re­search jour­nal Cur­rent Bi­ol­o­gy al­so sug­gests that this beast and its kin—giant dino­saurs known as sau­ro­pods—could have har­bored enough meth­ane-making mi­crobes in their guts to make a sub­stan­ti­al cli­mate im­pact.

“A sim­ple math­e­mat­i­cal mod­el sug­gests that the mi­crobes liv­ing in sau­ro­pod di­no­saurs may have pro­duced enough meth­ane to have an im­por­tant ef­fec­t,” said Dave Wilkin­son of Liv­er­pool John Moores Uni­vers­ity in the U.K. “Our cal­cula­t­ions sug­gest that these di­no­saurs could have pro­duced more meth­ane than all mod­ern sources—both nat­u­ral and man-made—put to­geth­er.”

Meth­ane and oth­er green­house gas­es tend to warm the cli­mate by trap­ping heat in the at­mos­phere, sci­en­tists say.

Dis­tinc­tive for their enor­mous size and long necks, sau­ro­pods were wide­spread about 150 mil­lion years ago. As in cows, meth­ane-producing mi­crobes aided the sau­ro­pods’ di­ges­tion by fer­ment­ing their plant food. Wilkin­son and study co­au­thor Graeme Rux­ton from the Uni­vers­ity of St An­drews, U.K. were stu­dying sau­ro­pod ecol­o­gy when a ques­tion dawned on them: If mod­ern cows pro­duce enough meth­ane gas to be of in­ter­est to cli­mate sci­en­tists, what about sau­ro­pods? They teamed up with meth­ane ex­pert Euan Nis­bet at the Uni­vers­ity of Lon­don to work out the num­bers.

“Clearly, try­ing to es­ti­mate this for an­i­mals that are un­like an­y­thing liv­ing has to be a bit of an ed­u­cat­ed guess,” Wilkin­son said.

Phys­i­ol­o­gists have stud­ied meth­ane pro­duc­tion from a range of mod­ern an­i­mals to de­rive equa­t­ions that pre­dict meth­ane pro­duc­tion from an­i­mals of dif­fer­ent sizes. It turns out those cal­cula­t­ions de­pend only on the an­i­mal’s weight. A me­di­um-sized sau­ro­pod weighed over 20 tons. Us­ing avail­a­ble es­ti­mates of popula­t­ion dens­i­ties, the sci­en­tists cal­culated glob­al meth­ane emis­sions from sau­ro­pods to have been 520 mil­lion met­ric tons year­ly, com­pa­ra­ble to to­tal mod­ern meth­ane emis­sions.

Be­fore mod­ern in­dus­try took off, meth­ane emis­sions were roughly 200 mil­lion met­ric tons a year. Mod­ern ru­mi­nant an­i­mals, in­clud­ing cows, goats, gi­raffes, and oth­ers, pro­duce about one-fourth to one-half that amount. The stu­dy’s con­clu­sions not only show “just how strange and won­der­ful the work­ings of the plan­et are,” but al­so serve as a use­ful re­minder for the im­por­tance of mi­crobes and meth­ane for glob­al cli­mate, the re­search­ers wrote.

Scientists: birds are just baby dinosaurs, in a way

There’s a good rea­son birds are so much cut­er and less threat­en­ing than their scary an­ces­tors—the di­no­saurs—if new re­search is cor­rect.

It’s be­cause birds are, in a sense, di­no­saurs stuck in ba­by mode.

“When we look at birds, we are ac­tu­ally look­ing at ju­ve­nile di­no­saurs” to a great de­gree, said Arkhat Abzhanov of Har­vard Uni­vers­ity, co-au­thor of a re­port on the find­ings.

Skulls of three types of ar­chosaur—al­li­ga­tor, prim­i­tive di­no­saur, and ear­ly bird. The left col­umn rep­re­sents ju­ve­niles and the right col­umn rep­re­sents adults. (Im­age cour­te­sy U. of Tex­as at Aus­tin)

Abzhanov and col­leagues an­a­lyzed doz­ens of bird and di­no­saur skulls. They found that rath­er than take years to reach sex­u­al matur­ity, as many di­no­saurs did, birds sped up the clock­—some spe­cies take as lit­tle as 12 weeks to ma­ture—al­low­ing them to re­tain the phys­i­cal char­ac­ter­is­tics of ba­by di­no­saurs.

The report ap­peared May 27 in an on­line edi­tion of the jour­nal Na­ture.

In ev­o­lu­tion, spe­cies change be­cause some char­ac­ter­is­tics are more use­ful than oth­ers in a given envi­ron­ment. Thus in­di­vid­u­als with more of those traits thrive, and through their off­spring, spread those fea­tures through a popula­t­ion. In­di­vid­u­als lack­ing those traits grad­u­ally drop out. As this goes on, spe­cies can even­tu­ally be­come nearly un­rec­og­niz­a­ble com­pared to their old selves.

Most ev­o­lu­tion­ary re­search has fo­cused on the phys­i­cal struc­ture of or­gan­isms, but “what is in­ter­est­ing about this re­search,” Abzhanov said, is that it il­lus­trates how great changes can oc­cur “simply by chang­ing the rel­a­tive tim­ing of events in a crea­ture’s de­vel­op­ment.” Thus, he added, “na­ture has pro­duced the mod­ern bird—an en­tirely new crea­ture and one that, with ap­prox­i­mately 10,000 spe­cies, is to­day the most suc­cess­ful group of land ver­te­brates on the plan­et.”

Di­no­saurs have long snouts and mouths bristling with teeth, while birds have pro­por­tion­ally larg­er eyes and brains. But what in­spired the study was the real­iz­a­tion that skulls of mod­ern birds and ju­ve­nile di­no­saurs show sur­pris­ing si­m­i­lar­ity, re­search­ers said.

“No one had told the big sto­ry of the ev­o­lu­tion of the bird head be­fore,” said Bhart-Anjan Bhullar, a Har­vard doc­tor­al stu­dent and first au­thor of the stu­dy. “There had been a num­ber of smaller stud­ies that fo­cused on par­tic­u­lar points of the anat­o­my, but no one had looked at the en­tire pic­ture. ... When you do that, you see the ori­gins of the fea­tures that make the bird head spe­cial lie deep in the histo­ry of the ev­o­lu­tion of Ar­chosaurs, a group of an­i­mals that were the dom­i­nant, meat-eating an­i­mals for mil­lions of years.”

With col­leagues at The Uni­vers­ity of Tex­as at Aus­tin, the re­search­ers con­ducted CT scans on doz­ens of skulls, rang­ing from mod­ern birds to theropod­s—the di­no­saurs most closely re­lat­ed to birds—to early di­no­saur spe­cies. By mark­ing var­i­ous “land­marks” in the skull the scien­tists tracked how the over­all shape changed over mil­lions of years.

“We ex­am­ined skulls from the en­tire line­age that gave rise to mod­ern birds,” Abzhanov said. “We looked back ap­prox­i­mately 250 mil­lion years, to the Ar­chosaurs, the group which gave rise to crocodiles and al­li­ga­tors as well as mod­ern birds.” 

It turned out, he said, that while early di­no­saurs, even those closely re­lat­ed to mod­ern birds, un­dergo vast struc­tur­al changes as they ma­ture, the skulls of ju­ve­nile and adult birds re­main re­markably sim­i­lar. In the case of mod­ern birds, Abzhanov said, the change is the re­sult of a pro­cess known as pro­ge­n­e­sis, which causes an an­i­mal to reach sex­u­al matur­ity ear­li­er.

“To really study some­thing you have to look at its whole ex­ist­ence, and un­der­stand that one por­tion of its life can be parceled out and made in­to the en­tire life­span of a new, and in this case, radic­ally suc­cess­ful or­gan­is­m,” Bhullar said.

75% of African lion habitat gone, study says

Li­ons have lost three-quarters of their orig­i­nal nat­u­ral hab­i­tat in Af­ri­ca as peo­ple have tak­en it over for their own pur­poses, ac­cord­ing to a new stu­dy.

The re­port reaches a som­ber con­clu­sion: West­ern Af­ri­ca, in par­tic­u­lar, must be giv­en mon­ey to pro­tect li­ons. Billed as the fullest as­sess­ment to date on the state of Af­ri­can sa­van­nah, or grass­land, hab­i­tat, the re­port says the hab­i­tat loss has dev­as­tat­ed li­on popula­t­ions.

A li­on in West Af­ri­ca. (Cred­it: Phi­lipp Hen­schel/­Pan­the)

“From an orig­i­nal ar­ea a third larg­er than the con­ti­nen­tal Un­ited States, only 25 per­cent re­mains,” said Stu­art Pimm of Duke Uni­vers­ity in Dur­ham, N.C., co-author of the re­port, which ap­pears on­line this week in the jour­nal Bio­divers­ity and Con­serva­t­ion. Primm and oth­er sci­en­tists co­or­di­nated by the uni­vers­ity co-wrote the re­port with Phi­lipp Hen­schel, co­or­di­na­tor of the New York-based Pan­ther­a's Li­on Pro­gram Sur­vey.

The group used Google Earth's high-resolution sat­el­lite im­age­ry to ex­am­ined sa­van­nah across Af­ri­ca, which com­prises the ma­jor­ity of the li­on's cur­rent range. They al­so an­a­lyzed hu­man popula­t­ion dens­ity da­ta to iden­ti­fy ar­e­as of suit­a­ble hab­i­tat. They iden­ti­fied just 67 iso­lat­ed re­gions continent-wide where sig­nif­i­cant li­on popula­t­ions may per­sist. Of these, only 15 were es­ti­mat­ed to main­tain at least 500 li­ons.

The study al­so found that in West Af­ri­ca, where the spe­cies is clas­si­fied as Re­gion­ally En­dan­gered on the Red List of Threat­ened Spe­cies, few­er than 500 li­ons re­main, scat­tered across eight iso­lat­ed re­gions.

“Li­ons have been hit hard­est in West Af­ri­ca, where lo­cal go­vernments of­ten lack di­rect in­cen­tives to pro­tect them,” Hen­schel said. “While li­ons gen­er­ate billi­ons of tour­ist dol­lars across East­ern and South­ern Af­ri­ca, spur­ring go­vernments to in­vest in their pro­tection, wildlife-based tour­ism is only slowly de­vel­op­ing in West Af­ri­ca. Cur­rently li­ons still have lit­tle eco­nom­ic val­ue in the re­gion, and West Af­ri­can go­vernments will re­quire sig­nif­i­cant for­eign as­sis­tance in sta­bi­liz­ing re­maining popula­t­ions un­til sus­tain­a­ble lo­cal con­serva­t­ion ef­forts can be de­vel­ope­d.”

Pan­thera col­la­bo­rates in the Washington-based Na­t­ional Ge­o­graph­ic So­ci­ety's Big Cats In­i­ti­a­tive, which is meant to ad­dress the most se­ri­ous threats fac­ing big cats in the wild and help chan­nel fi­nan­cial sup­port to well-de­signed con­serva­t­ion pro­grams.

Pill may cut HIV risk as much as 99%

Daily use of a pill ap­proved to pro­tect against HIV in­fec­tion cuts a man’s risk of get­ting the vi­rus by 99 per­cent, a new study in­di­cates.

The re­search al­so of­fers the first ev­i­dence that even im­pe­r­fect ad­her­ence to the treat­ment reg­i­men can pro­vide a big re­duc­tion in the risk of ac­quir­ing the vi­rus, which causes AIDS. Par­ti­ci­pants in the re­search were found to be able to cut their HIV in­fec­tion risk by 76 pe­r­cent merely by tak­ing two doses a week.

The stu­dy, pub­lished in the Sept. 12 on­line is­sue of the re­search jour­nal Sci­ence Transla­t­ional Med­i­cine, ex­am­ines the ef­fec­tive­ness of a FDA-ap­proved drug known as teno­fovir diso­proxil fu­marate (brand name Tru­vada).

The re­search builds on a 2010 study by Rob­ert Grant at the Uni­vers­ity of Cal­i­for­nia, San Fran­cis­co and the Glad­stone In­sti­tute in San Fran­cis­co, along with col­leagues. The team found that Tru­vada—which had been used for years to treat HIV-positive pa­tients—could al­so pre­vent new in­fec­tions in peo­ple likely to come in con­tact with the vi­rus.

But ques­tions about the drug’s real-world ef­fec­tive­ness re­mained—in par­ticu­lar con­cern­ing the is­sue of ad­her­ence to a reg­i­men of a pill a day. “There was con­cern that the pro­tective ef­fect of Tru­vada was frag­ile, and that in­di­vid­u­als tak­ing the drug would need to ad­here pe­r­fectly to daily reg­i­men for it to work,” said Grant. “This new study sug­gests that Tru­vada can help block the vi­rus even if the pe­r­son on a daily reg­i­men does­n’t al­ways ad­here pe­r­fectly.”

The study ex­am­ined the risk of HIV ac­qui­si­tion in men who have sex with men. Par­ti­ci­pants dif­fer­ent doses of the drug. Men came in­to a clin­ic eve­ry day and were giv­en ei­ther two pills per week, four pills per week or se­ven pills per week. The re­search­ers then com­pared drug con­centra­t­ions from their study to drug con­centra­t­ions from a pre­vi­ous stu­dy.

The re­search team es­ti­mates that par­ti­ci­pants could re­duce their risk of HIV by 76 pe­r­cent tak­ing two doses per week, 96 pe­r­cent by tak­ing four doses per week, and 99 pe­r­cent by tak­ing se­ven doses per week.

The tim­ing of the dos­ing rel­a­tive to sex­u­al in­ter­course likely mat­ters, based on re­search done in non-human pri­ma­tes, al­though this could not be in­ves­t­i­gated in de­tail in peo­ple, the re­search­ers added. High­er drug con­centra­t­ions and more fre­quent use may be re­quired for wom­en be­cause the drugs are not con­centrated as much in the fe­male gen­i­tal tract, the au­thors not­ed.

“Pa­tients should still take one pill a day to achieve the best re­sults, and we en­cour­age peo­ple to ex­plore mul­ti­ple meth­ods to pre­vent HIV—such as reg­u­lar con­dom use, early treat­ment of HIV in­fec­tion in part­ners, good com­mu­nica­t­ion and male cir­cum­ci­sion,” Grant said. “We hope that our find­ings lead to more ef­fective use of pre­vention tools that fi­nally squash the HIV/AIDS epi­dem­ic.”

Gene that may have helped make people smart ID’d

Re­search­ers have found a gene that they say helps ex­plain how hu­mans evolved from apes.

Called miR-941, it seems to have played a cru­cial role in brain de­vel­op­ment and may shed light on how we learn­ed to use tools and lan­guage, the sci­en­tists say. They add that it's the first time a new gene, car­ried only by peo­ple and not by apes, has been shown to have a spe­cif­ic func­tion in the body.

“This new mol­e­cule sprang from no­where at a time when our spe­cies was un­der­go­ing dra­mat­ic changes: liv­ing long­er, walk­ing up­right, learn­ing how to use tools and how to com­mu­ni­cate,” said Mar­tin Tay­lor of the Uni­vers­ity of Ed­in­burgh in Scot­land, who led the stu­dy. “We're now hope­ful that we will find more new genes that help show what makes us hu­man.”

The gene has been found to be highly ac­tive in two ar­eas of the brain that con­trol our de­ci­sion mak­ing and lan­guage abil­i­ties. The study sug­gests it could have a role in the ad­vanced brain func­tions that make us hu­man.

A team at the uni­vers­ity com­pared the hu­man ge­nome to 11 oth­er spe­cies of mam­mals, in­clud­ing chim­panzees, go­ril­las, mouse and rat, to find the dif­fer­ences be­tween them. The re­sults, pub­lished in the jour­nal Na­ture Commu­nica­t­ions, in­di­cate the gene is un­ique to hu­mans. The re­search­ers say it emerged be­tween six and one mil­lion years ago, af­ter the hu­man line­age had branched off from apes.

Most dif­fer­ences be­tween spe­cies oc­cur as a re­sult of changes to ex­ist­ing genes, or the du­plica­t­ion and de­le­tion of genes. But sci­en­tists say this gene emerged fully func­tional out of non-coding ge­net­ic ma­te­ri­al, pre­vi­ously termed “junk DNA,” in a startlingly short time in evo­lu­tion­ary terms.

http://wrd.cm/1gVYv0C

Stunning photos show the solar flare explosions that happened all weekend long on the sun. (Image: NASA/SDO)

“Cloud map” of planet beyond our system a first

As­tro­no­mers us­ing da­ta from NASA’s Kep­ler and Spitzer space tele­scopes have cre­at­ed what they call the first cloud map of a plan­et be­yond our so­lar sys­tem. It’s a siz­zling, Ju­pi­ter-like world known as Kep­ler-7b.

High clouds in the west and clear skies in the east mark the plan­et, the map in­di­cates. Pre­vi­ous stud­ies from Spitzer have re­sulted in tem­per­a­ture maps of plan­ets or­bit­ing oth­er stars, but this is the first look at cloud struc­tures on a dis­tant world.

This diagram represents the cloud map of Kepler 7b, left, with Jupiter shown alongside for size comparison. (Image credit: NASA/JPL-Caltech/MIT)

“By ob­serv­ing this plan­et with Spit­zer and Kep­ler for more than three years, we were able to pro­duce a very low-re­so­lu­tion ‘map’ of this gi­ant, gas­e­ous plan­et,” said Brice-Oli­vier De­mory of Mas­sa­chu­setts In­sti­tute of Tech­nol­o­gy in Cam­bridge.

He is the lead au­thor of a pa­per on the work, ac­cept­ed for pub­lica­t­ion in the jour­nal As­t­ro­phys­i­cal Jour­nal Let­ters.

“We would­n’t ex­pect to see oceans or con­ti­nents on this type of world, but we de­tected a clear, re­flec­tive sig­na­ture that we in­ter­preted as clouds.”

Kep­ler has dis­cov­ered more than 150 exoplan­ets, which are plan­ets out­side our so­lar sys­tem. Kep­ler-7b, about 50 per­cent wid­er than Ju­pi­ter, was one of the first. The tel­e­scope is out of com­mis­sion for plan­et-hunting, but as­tro­no­mers are still por­ing over al­most four years’ worth of old da­ta.

Kep­ler’s visible-light ob­serva­t­ions of Kep­ler-7b’s moon-like phases led to a rough map of the plan­et that showed a bright spot on its west­ern hem­i­sphere. But these da­ta alone weren’t enough to de­ci­pher wheth­er the bright spot was com­ing from clouds or heat, ac­cord­ing to the as­tro­no­mers. The Spitzer tel­e­scope helped an­swer that.

Like Kep­ler, Spitzer can fix its gaze at a star sys­tem as a plan­et or­bits around the star, gath­er­ing clues about the plan­et’s at­mos­phere. Spitzer’s abil­ity to de­tect in­fra­red light, a low-energy form of light in­vis­i­ble to the un­aided eye, means it was able to meas­ure Kep­ler-7b’s tem­per­a­ture, es­ti­mat­ing it to be be­tween 1,500 and 1,800 de­grees Fahr­en­heit (1,100 and 1,300 Kelv­in).

This is rel­a­tively cool for a plan­et that or­bits so close to its star – less than 1/15 as close to its sun as we are to ours – and ac­cord­ing to as­tro­no­mers, too cool to be the source of light Kep­ler ob­served. In­stead, they de­ter­mined, light from the plan­et’s star is bounc­ing off cloud tops on the plan­et’s west side.

“Kep­ler-7b re­flects much more light than most gi­ant plan­ets we’ve found, which we at­trib­ute to clouds in the up­per at­mos­phere,” said Thom­as Barc­lay, Kep­ler sci­ent­ist at NASA’s Ames Re­search Cen­ter in Mof­fett Field, Ca­lif. “Un­like those on Earth, the cloud pat­terns on this plan­et do not seem to change much over time—it has a re­markably sta­ble cli­mate.”

The find­ings are seen as an early step to­ward us­ing si­m­i­lar tech­niques to study the at­mos­pheres of plan­ets more like Earth in make­up and size.

“Cloud map” of planet beyond our system a first

As­tro­no­mers us­ing da­ta from NASA’s Kep­ler and Spitzer space tele­scopes have cre­at­ed what they call the first cloud map of a plan­et be­yond our so­lar sys­tem. It’s a siz­zling, Ju­pi­ter-like world known as Kep­ler-7b.

High clouds in the west and clear skies in the east mark the plan­et, the map in­di­cates. Pre­vi­ous stud­ies from Spitzer have re­sulted in tem­per­a­ture maps of plan­ets or­bit­ing oth­er stars, but this is the first look at cloud struc­tures on a dis­tant world.

This diagram represents the cloud map of Kepler 7b, left, with Jupiter shown alongside for size comparison. (Image credit: NASA/JPL-Caltech/MIT)

“By ob­serv­ing this plan­et with Spit­zer and Kep­ler for more than three years, we were able to pro­duce a very low-re­so­lu­tion ‘map’ of this gi­ant, gas­e­ous plan­et,” said Brice-Oli­vier De­mory of Mas­sa­chu­setts In­sti­tute of Tech­nol­o­gy in Cam­bridge.

He is the lead au­thor of a pa­per on the work, ac­cept­ed for pub­lica­t­ion in the jour­nal As­t­ro­phys­i­cal Jour­nal Let­ters.

“We would­n’t ex­pect to see oceans or con­ti­nents on this type of world, but we de­tected a clear, re­flec­tive sig­na­ture that we in­ter­preted as clouds.”

Kep­ler has dis­cov­ered more than 150 exoplan­ets, which are plan­ets out­side our so­lar sys­tem. Kep­ler-7b, about 50 per­cent wid­er than Ju­pi­ter, was one of the first. The tel­e­scope is out of com­mis­sion for plan­et-hunting, but as­tro­no­mers are still por­ing over al­most four years’ worth of old da­ta.

Kep­ler’s visible-light ob­serva­t­ions of Kep­ler-7b’s moon-like phases led to a rough map of the plan­et that showed a bright spot on its west­ern hem­i­sphere. But these da­ta alone weren’t enough to de­ci­pher wheth­er the bright spot was com­ing from clouds or heat, ac­cord­ing to the as­tro­no­mers. The Spitzer tel­e­scope helped an­swer that.

Like Kep­ler, Spitzer can fix its gaze at a star sys­tem as a plan­et or­bits around the star, gath­er­ing clues about the plan­et’s at­mos­phere. Spitzer’s abil­ity to de­tect in­fra­red light, a low-energy form of light in­vis­i­ble to the un­aided eye, means it was able to meas­ure Kep­ler-7b’s tem­per­a­ture, es­ti­mat­ing it to be be­tween 1,500 and 1,800 de­grees Fahr­en­heit (1,100 and 1,300 Kelv­in).

This is rel­a­tively cool for a plan­et that or­bits so close to its star – less than 1/15 as close to its sun as we are to ours – and ac­cord­ing to as­tro­no­mers, too cool to be the source of light Kep­ler ob­served. In­stead, they de­ter­mined, light from the plan­et’s star is bounc­ing off cloud tops on the plan­et’s west side.

“Kep­ler-7b re­flects much more light than most gi­ant plan­ets we’ve found, which we at­trib­ute to clouds in the up­per at­mos­phere,” said Thom­as Barc­lay, Kep­ler sci­ent­ist at NASA’s Ames Re­search Cen­ter in Mof­fett Field, Ca­lif. “Un­like those on Earth, the cloud pat­terns on this plan­et do not seem to change much over time—it has a re­markably sta­ble cli­mate.”

The find­ings are seen as an early step to­ward us­ing si­m­i­lar tech­niques to study the at­mos­pheres of plan­ets more like Earth in make­up and size.