- published: 30 Jun 2017
- views: 3982
Birds (class Aves) are a group of endothermic vertebrates, characterised by feathers, a beak with no teeth, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a lightweight but strong skeleton. Birds live worldwide and range in size from the 5 cm (2 in) bee hummingbird to the 2.75 m (9 ft) ostrich. They rank as the class of tetrapods with the most living species, at approximately ten thousand, with more than half of these being passerines, sometimes known as perching birds or, less accurately, as songbirds.
The fossil record indicates that birds are the last surviving dinosaurs, having evolved from feathered ancestors within the theropod group of saurischian dinosaurs. True birds first appeared during the Cretaceous period, around 100 million years ago, and the last common ancestor is estimated to have lived about 95 million years ago. DNA-based evidence finds that birds radiated extensively around the time of the Cretaceous–Paleogene extinction event that killed off the non-avian dinosaurs. Birds in South America survived this event and then migrated to other parts of the world via multiple land bridges while diversifying during periods of global cooling. Primitive bird-like "stem-birds" that lie outside class Aves proper, in the group Avialae, have been found dating back to the mid-Jurassic period. Many of these early stem-birds, such as Archaeopteryx, were not yet capable of fully powered flight, and many retained primitive characteristics like toothy jaws in place of beaks and long bony tails.
World is a common name for the whole of human civilization, specifically human experience, history, or the human condition in general, worldwide, i.e. anywhere on Earth or pertaining to anywhere on Earth.
In a philosophical context it may refer to:
In a theological context, world usually refers to the material or the profane sphere, as opposed to the celestial, spiritual, transcendent or sacred. The "end of the world" refers to scenarios of the final end of human history, often in religious contexts.
World history is commonly understood as spanning the major geopolitical developments of about five millennia, from the first civilizations to the present.
World population is the sum of all human populations at any time; similarly, world economy is the sum of the economies of all societies (all countries), especially in the context of globalization. Terms like world championship, gross world product, world flags etc. also imply the sum or combination of all current-day sovereign states.
Garden Birds in The Gentle Rain - One Hour of Relaxing Rain and Bird Sounds Filmed in slow motion using a Panasonic HC V750 Camcorder Video Produced by Paul Dinning - Wildlife in Cornwall Filmed on May 17th 2017
This is one of a series of Nature Sounds videos designed for various needs:- as a calming sound to play in the background while studying or as a soothing sound to play while you sleep. These videos can be used for many relaxation requirements and meditation, let me know how you use this video. With each video there will be a tip to help you with your studying or how to achieve a relaxed sleep. Gifts to buy:- Your favourite ‘Nature Scene’ Soundscapes as 8 Hour mp3 downloads. https://gumroad.com/relaxingnaturesounds 1 Hour HD Nature Videos as mp4 downloads. https://gumroad.com/relaxingnaturevideos Natures calming sounds and vision captured for your viewing pleasure. Great classic novels as Audio Book mp3 downloads or as unique sensory videos https://gumroad.com/childrensaudiobooks With...
The Ultimate Videos of Birds for Cats To Watch The birds in the video are - First Clip - Eurasian Jays with a Magpie sneaking in towards the end. 2:15 - Nuthatches, Coal Tits and Blue Tits. 3:19 - Crow, Coal Tit, Nuthatch and Chaffinch. 4:27 - European Goldfinches. 8:14 - Great Tits, Nuthatches, Coal Tits, Robins. 11:47 - Nuthatch, Robin, Blue Tit, Great Tit, Coal Tit. 13:31 - Robins. 15:31 - Female Blackbird, Coal Tit, Great Tit, Blue Tit and Nuthatch. Video Produced by Paul Dinning - Wildlife in Cornwall
19 of the funniest birds you'll see this week. The Pet Collective is home to the top trending clips, most entertaining memes, and funniest animal videos online. Simply put, we think animals are the best ever. If you agree, let’s make it YouTube official right here, right meow: Subscribe to The Pet Collective: http://bit.ly/tpcsub Website: http://www.thepetcollective.tv Facebook: http://www.facebook.com/thepetcollective Instagram: http://www.instagram.com/petcollectivetv Pinterest: http://pinterest.com/petcollectivetv/ Want to submit your own awesome pet vid to us? There's a link for that! jukinmedia.com/video-submissions Watch the Originals: https://www.youtube.com/watch?v=6_-4KArFR08 https://www.youtube.com/watch?v=t1wAjcWHkDY https://www.youtube.com/watch?v=pLJegq01S6A https://www.y...
Entertainment Videos for Cats and Their People to Watch : Birds on The Little Hill - Featuring Chaffinch, Robin, Blue Tit, Great Tit, Coal Tit, Dunnock and Nuthatch Video Produced by Paul Dinning - Wildlife in Cornwall Filmed on May 17th 2017
Come check out this brand new all birds weekly compilation filled with funny clips, bloopers and moments of ducks, parrots, chickens, turkeys, seagulls and other funny birds.
5 Most Unique Birds That Exist Around The World! Description: If you thought bird watching was not how you’d spend your Saturday afternoon, or your free time, you may want to reconsider. This art is one that is prized by millions across the globe, and for a good reason. It takes a lot of travelling to see all the amazing birds out there. We figured that much and are bringing the experience at the comfort of your couch. Sit back and enjoy the spectacle of the 5 Most Unique Birds That Exist Around The World! Ready? Well, lets begin! 1. Andean Cock-of-the-Rock This one is a beauty. This colorful creature resides in the Andes Mountains of South America. Its appearance is pleasant to behold but also serves as an attraction to preying eagles and jaguars. Now that is just not fair. Because of...
Birds, they're walking all around
Birds, they're making little sounds
Have you seen any birds today
I will blow those birds away
Birds, birds, birds, birds
Worms, they're sneaking underground
Worms, they're making tiny sounds
Dirt, is what they eat
Rocks and stones make a worm complete
Worms, worms, worms, worms
Birds, they're looking pretty cute
Birds, I see 'em, I shoot
Have you seen any birds today
I will blow those birds away
Birds, birds, birds, birds