BiOLOGY (4th Video) Planet of Life (Creatures of the Skies)

behind the coral reef agency dawn break softly on a quietly along the shoreline tropical groves teeming with life are beginning to stir on this day the forest will awaken to the cries of a newcomer archaeopteryx the world's oldest bird 150 million years ago the descendants of creatures from the land and sea first took to the skies today more than 9,000 species of birds inhabit the planet their plumage a masterpiece of design grabbing than perhaps the ultimate freedom flanked the origin birds even today is somewhat of an evolutionary mystery but Archaeopteryx may have offered scientists a key the earth 150 million years ago for eons only one giant supercontinent stretched across the planet now as it slowly divided distinct bodies of land were being shaped into the continents that would eventually become Eurasia and North America at the time the dinosaur was king animals of epic proportion grown throughout northern Giants feasting on lush forest land had spread from coast to coast but to the east a completely different scenario was unfolding situated much farther south than it is today Eurasia was largely underwater tropical islands with palm like ferns dotted the coastline in the Jurassic period the sky was the domain of the so-called winged lizard pterosaur it was the first vertebrate to fly terrasaur is probably descended from small reptiles or dinosaurs forming the first successful line of flying creatures how animals like Pterodactylus learned to fly is unknown developing a lighter skeletal structure than land-bound vertebrates was the first step and an arm with one extremely elongated finger to support a large single wing its wing had no feathers just a large fibrous membrane folded compactly these giant wings allowed pterosaur enough mobility to climb trees hollow bones with sturdy but lightweight support were another new evolutionary design pterosaurs flew like lighters soaring on the tropical currents along the shoreline sharp eyed hunters they scoured the coral reefs and lagoons teeming with fish mollusks starfish and other sea life sighting prey they swooped to the surface with their long beaks escaped with their catch but while the pterosaur reigns sovereign over the skies another attempted flight was underway these rolling hills in the Bavarian countryside of southern Germany were once covered by tropical Lagoon over time their soft muddy sediments hardened into beds of limestone today that limestone is quarried in the town of Sohn - for use in building construction but the slabs that peel away in thin sheets have also yielded remarkable finds for paleontologists hidden in the layers of limestone are perfectly preserved fossils that may help unravel the mysteries of our past dr. peter van hopper of the Bavarian State Museum has been studying this site she's forgiven in the film oints ich meet Kyle we're now at the bottom of the ancient sea this formation was made by the accumulation of the Jurassic say 150 million years ago come here Anna she's forgiven me there are about 90 meter thick layers of limestone and these lie in each formation like plates the rocks were made of fine lime sponges and they covered the ground and formed a lagoon at the same time from open seas and from the land organisms animals and plants were washed to this place and accumulated in this Lagoon sind up Gustave they died and dried and accumulated on the ground buried in the mud and the muddy layers that covered the ground preserved the fossils as a result this mud on the ground turned to rock from the pressure of the more than 600 different kinds of life forms including the pterosaur have left perfect imprints in these rocks among them one unusual fossil of a creature discovered more than a century ago an animal that ignited debate in 19th century scientific circles about the new theory of evolution it was an imprint of a single feather less than three inches long next to surface of fossil without disco this animal appeared to have feathers like a bird but unlike birds a long tail perhaps most puzzling of all its legs looked reptilian with this combination of features the bones could not be classified as pterosaur or bird the fossil was named Archaeopteryx or ancient winged because of its feather imprint whether this animal was a bird or reptile was anyone's guess bird or reptile the debate over Archaeopteryx continued at Full Tilt finally the fossil landed at the British Museum of Natural History it's superintendent Mercer Richard Owen a leading 19th century anatomist examining the fossil of Archaeopteryx he made his pronouncement unequivocally a bird Oh one notice the be shaped bone in the center of the fossil imprint he realized it was a fur kuma a strangely shaped collarbone found only in birds an Archaeopteryx fossil found in 1877 clearly showed the presence of wings the first specimens found were so perfectly preserved that they were thought to be forgeries archaeopteryx has lizard-like teeth and another feature not found in modern birds 3 sharply hooked claws and it's wings despite its somewhat reptilian features this indeed was the world's first earned the Orinoco River in Venezuela a habitat resembling Archaeopteryx is primitive nesting ground this is a home to another ancient bird with remarkably similar features called Watson this spiky crested bird is the size of a chicken the adult bird has no claws in its wings but the newborn chick has hooked claws just like Archaeopteryx the only modern bird with vestiges of its evolutionary past with these claws the young chicks move deftly from one branch to another evidence like this convinced some scientists that Archaeopteryx evolved from a creature that lived in the trees experts still have many conflicting theories about the origins of bird at the University of Kansas dr. Larry Martin describes how he thinks birds evolved Martin believes that primitive arboreal reptiles developed feathers to help them glide through the treetops he's convinced that a relative of lago su cos a reptile that lived more than 200 million years ago is the ancestor of birds the proto birds would have been small lizard like reptiles that lived in trees I don't think that they would have been very well adapted for bipedal locomotion on the ground it seems at least reasonable to suppose that feathers originally were used as flight structures if an animal can leap or glide from tree to tree it could move quickly and efficiently through the forest dr. Martin says that scales covering small arboreal reptiles gradually evolved into feathers allowing lag asuka's to increase the range of its jumps though they look entirely different both scales and feathers are made of the same substance a protein called keratin reptiles originally developed tough scales to protect the skin but over time Martens and castes and their transformation into feathers gave them freedom to fly through the forest but no intermediary fossil has ever been found linking reptiles to Archaeopteryx the question remains if the membrane wing pterosaur could fly without feathers why not Birds for 20 years the Archaeopteryx fossil preserved at the Jurassic Museum and Bavaria was mistaken for an entirely different animal a dinosaur called Compsognathus Compsognathus was a carnivorous dinosaur about two feet long that lived in the Late Jurassic period dr. John Ostrom of Yale University is one of the world's leading authorities on Dinosaurs he believes that the origin of birds rest with a small highly active dinosaur not a reptile dr. Ostrom has done a comparative analysis of Archaeopteryx and Compsognathus and identified 20 significant points of similarity between the two the skull the backbone the pelvic girdle and almost every other feature of the skeleton as certainly Archaeopteryx suggests its skeletal Anatomy clearly indicates an active creature it may then have been warm-blooded or endothermic and if that's the case then feathers the early feathers the initial feathers may have served some endothermic role of it perhaps as a form of primitive insulation Post from speculates why dinosaurs may have evolved into feathered creatures with a bird-like metabolism he argues Compsognathus had to maintain a consistently high body temperature to keep up its activity level so it's scales evolved into feathers for insulation dr. hoster believes that these feathered dinosaurs were the forerunners of birds birds can fly using their forearms or wings and they can use their legs and feet as legs to run about no other creature other than certain insects have two completely independent means of locomotion I think that's one of the reasons why birds are so successful today where did birds come from after more than a century of debate there is no conclusive evidence to verify either theory how and why feathers finally evolved is one of the great unknowns but eventually birds would play a major role in virtually every habitat across the globe archeopteryx the planets first bird may not have flown gracefully according to some scientists but it may have been better equipped to fly than previously imagined ornithologist Alan fiducia of the University of North Carolina has been studying the fossilized imprints of Archaeopteryx feathers comparing them with those of modern birds an evolutionary line is generally punctuated by a trail of fossils in different stages of development no such link exists in birds these are photographs of the left wing of the Berlin specimen of Archaeopteryx and they're quite important because they show the wing of a modern bird virtually unchanged in any significant detail in a hundred and fifty million years and they show a number of other characteristics if we look closely at the microstructure of these feathers we find that in fact even in their microstructure they're unchanged this is the feather imprint of the first Archaeopteryx fossils discovered in 1861 the shaft of the feather from base to tip is a little off-center these are the feathers of a modern turbine dog just like the Archaeopteryx specimen its feathers are asymmetrical with off-centered shafts viewed in cross section a single feather undulates in a gentle s-curve this anatomical feature is shared by wall birds that fly the secret to flight was in fact this asymmetry how is the construction of the feather related to flight dr. Akira Zuma of the University of Tokyo conducted this experiment first flat plates with the central axis are placed in a row they represent the wings of a flightless bird these plates are then exposed to wind pummeled by wind the plates Bend in different directions without stabilizing flight with such wings would be impossible next an experiment with undulating plates bearing an off-centered axis to simulate the wings of Archaeopteryx and other birds that fly when wind is applied all the plates rise and stabilize each plate perfectly aligned to form the shape of a wing these undulating plates are stable even when exposed to strong air currents the wings of modern aircraft are designed on the basis of this aerodynamic shape 150 million years ago Archaeopteryx already had sophisticated wings with perfectly aligned feathers racing through the forest scientists believe Archaeopteryx was an agile runner unable yet to reach the heights Archaeopteryx was capable of some powered plant but far beyond the treetops terrasaur dominated the jurassic skies unlike Archaeopteryx pterosaurs had lighter bodies and hollow bones allowing them to sort to date only half a dozen Archaeopteryx fossils have ever been identified all from zone hoppin Germany in 1990 to another bird fossil was discovered in China since then bird fossils of a later generation have been found in greater numbers in the hills of Liaoning province in northeast china lie sediments from the early cretaceous period this was once a subtropical region like zone - with forests of ferns and palm trees encircling a large lake it is here that clues about the birds that came after Archaeopteryx surfaced next sonorous our Chinese bird is about four inches long scientists believe that sonorus was a forest dweller feeding on insects and small reptiles the skeletal structure reconstructed from the fossils closely resembles that of modern Birds compared to Archaeopteryx sigh Norris had smaller teeth shorter hooked claws on its wings and an almost non-existent tailbone another significant structural advancement was the appearance of a sternum but this newly developed breastbone it could develop stronger muscles to power its wings but like the ancient pterosaurs the most important anatomical feature observed in sonorous is hollow bone allowing for more efficient flight dr. Lau Ching Gong of the Natural History Museum of Beijing and yes I notices hollow bones are equipped with special air sacs those air sacs in the bones and in other parts of the body are connected to the lungs with this kind of system it was able to use the oxygen in the air to produce maximum energy air sacs are essential to sophisticated flight more than a hundred million years ago sigh Norris had nearly perfected the body structure found in modern-day birds a development that would eventually lead to an evolutionary explosion within the species when they branch off and achieved flight they seemed to undergo a burst of evolution something we've never seen before but due to the enormous ly physically restrictive demands of flight coupled with the extraordinarily high metabolic rate evolved by birds and feathers which are almost magical structures this produced an animal which had never been seen before by the end of the Late Cretaceous birds of all shapes and sizes had made their way across the globe and were gradually carving their niche in Earth's diverse ecosystems millions of years would elapse between the bursts of evolution that launched life in the seas the planet's first life forms were single-cell organisms the threat of extinction in the primordial ocean that individual cells to join forces with their neighbors sharing scarce nutrients essential for life to survive they would merge forming the new unicellular organism with two separate strands of DNA this was the beginning of sexual reproduction these integrated cells reproduce differently from the earliest life-forms which multiplied a sexually by replicating their own bodies first they copied both sets of DNA producing two identical pairs the strands of DNA approach each other randomly mixing their genes next the four sets of DNA each with a different genetic makeup split into individual sounds each cell in turn encounters another shuffling genes and fusing again into a distinct new body this cycle of communion and division is the essence of sex half a billion years ago the Cambrian seas surged with life though the environment helped to shape this explosion biological forces played an even greater role to adapt to the changing seas life-forms had developed the sexual reproductive system a system that created the conditions for progressive evolutionary change through genetic recombination birds developed feathers an adaptation unique to their species transforming both skeletal structure and Anatomy over the years they were able to streamline flight the process of evolutionary experimentation would ultimately allow birds to thrive and almost every habitat across the globe today in the sea on land and in the sky a tapestry of life unfolds the creatures on earth number well over 30 million different species the animal kingdom owes its existence to our unlikely ancestors in the primordial seas I'm passing on their hardness genes to generations that followed these simple multicellular organisms would transform the face of the planet birds are not the only winged creatures to take to the skies in a stunning array of shapes sizes and colors butterflies are models of diversity even within a single species here in the tropical rainforests of the Amazon lives an elusive butterfly known as the jewel of the forest catching it requires special bait in this case fermenting bananas because these butterflies like to feed on the juice of over ripe fruits a glisten is the name of this butterfly it's red and blue wing patterns stand out against the dark of the forest this red butterfly is also an actress each individual a glass has a unique wing pattern and color they all belong to the same species Lia's butterflies are constant innovators in the realm of genetic design every wing pattern comes in the three primary colors red blue and young but no two butterflies look alike these graceful creatures are indeed Forest Jews across the globe in Okinawa Japan ecologist Kim Chi you asougi believes that there are many important reasons for diversification mister uesugi has been studying the type of butterfly called mental ids polities it's a kind of swallowtail butterfly with a white striped pattern on its wings some of the females of this Swallowtail species have slightly different wing patterns red spots accentuate the white band this distinctive design is the result of generations of change in the gene pool the red spotted butterflies here are in the minority because the male's prefer the white striped females the Reds have fewer opportunities to breed these butterflies have predators birds like the bull balls in perpetual threat of attack some of the eye-catching white butterflies show battle scars chunks missing from their wings but for some reason the birds never select the red ones will the same thing happen under laboratory conditions red and white butterflies are placed in front of a bird simultaneously avoiding the red the bird again selects the white the results are repeated again and again in each case the red butterfly is left unharmed in Okinawa lives another kind of Swallowtail a poisonous butterfly called manymoon Agha the butterfly on the left closely resembles the red spotted mini lady's polities it is likely that bird shun the red butterfly mistaking it for the poisonous venom Onaga showing off its individual design the red spotted butterfly has greatly reduced its risk of predatory attacks sexual reproduction certainly creates diversity but oftentimes that diversity seems meaningless however the creation that seemingly meaningless diversity or mutation and it's staying power is of extreme importance and that it expands the possibility for survival when the environment changes genetic diversity provides assurance that life will continue surmounting the unpredictable and sometimes threatening forces of nature 150 million years ago Archaeopteryx was probably the only bird but by the end of the Cretaceous period birds had gained an evolutionary foot home meanwhile as the ancient pterosaurs dwindled their cousins the pterodactyl odds were increasing insides some had wing spans ranging up to 36 feet in 1985 American scientists using models conducted an experiment in the desert to find out how these giant pterodactyl loads flew model weighed 30 pounds and had a wingspan of 20 feet graceful fliers pterosaurs of the Late Cretaceous would catch the slightest draft with their huge wings and glide for hours at a time but by the end of that era 65 million years ago only three species of pterosaur remain at about that time an asteroid six miles wide crashed to earth with the force of an arsenal of nuclear bombs the collision triggered dramatic change in the Earth's ecology clouds of debris hovered in the atmosphere blocking out sunlight and for at least a year the planet endured a winter of destruction entire species and plants and animals perished among those lost to history with the kings of land and sky the dinosaurs the once thriving terror sir left in their wake were flowering plants insects mammals and birds dr. George Whitefield of Reading University in England is an expert in biomechanics he says the pterosaurs size may have contributed to their downfall we analysed Pteranodon as if he were a modern glider and calculated his strength upon how he would perform he can circle in very small circles because he flies slowly sinking very slowly because he's very efficient and this makes him a superb thermal soaring aircraft to go up in quite small light thermals the disadvantage of developing like this is that he is very large very weak and cannot fly very fast so if winds increase he's very badly placed while Birds develop their ability to fly by flapping their wings pterosaurs took a different route uniquely specialized creatures pterosaurs were able to glide on the most gentle currents by growing larger membrane wings but in strong winds they were like kites without strings you generally find that a series of species evolved to fit better and better and better the conditions in which they live and then if the conditions change they can't evolve back and you find that they've lost the variability needed to fit the new climate in this inter and islands case whereas the birds were much nearer the beginning of their evolution they had lots of variability available and they were both smaller and stronger and they could fold their wings complete so that the birds had a much better chance of living through the changing conditions to glide on the currents of evolution pterosaurs have become highly specialized animals faced with changes in their environment and no longer had means to adapt the age of the first flying creature had come to a close though the pterosaur had vanished for birds the age of flight had just become so perfectly adapted for life in the skies it is hard to imagine that birds had once descended from reptilian creatures in Germany where Archaeopteryx was discovered earth strata dating back 50 million years revealed numerous bird fossils this long-legged bird resembling a modern flamenco and fossils of 13 others including the eagle the Falcon and the crested Ibis have been unearthed today birds flourish in every corner of the globe from the polar regions to the equator millions of years since their arrival on the planet birds still remain unchallenged some migrate thousands of miles across oceans and continents each year others can soar as high as Earth's most magnificent mountain ranges graceful and strong they have pioneered territory untouched by other living creature driven by instincts unknown to man they made the evolutionary leap that has a loot of others overcoming the inescapable tug of gravity with the pterosaur long vanished birds alone are sovereign in the skies

Channel: CatholicVoting4Life

Views: 69,788

Rating: 4.6108599 out of 5

Keywords: Documentary, Discovery, Planet of Life, Birth of Earth

Id: 0wYmn_XDcRY

Length: 45min 42sec (2742 seconds)

Published: Sat May 24 2014