© iStock
In the report, noted scientist Ronald Breslow, Ph.D., discusses the century-old mystery of why the building blocks of terrestrial amino acids (which make up proteins), sugars, and the genetic materials DNA and RNA exist mainly in one orientation or shape. There are two possible orientations, left and right, which mirror each other in the same way as hands. This is known as "chirality."
In order for life to arise, proteins, for instance, must contain only one chiral form of amino acids, left or right. With the exception of a few bacteria, amino acids in all life on Earth have the left-handed orientation. Most sugars have a right-handed orientation. How did that so-called homochirality, the predominance of one chiral form, happen?
Breslow describes evidence supporting the idea that the unusual amino acids carried to a lifeless Earth by meteorites about 4 billion years ago set the pattern for normal amino acids with the L-geometry, the kind in terrestial proteins, and how those could lead to D-sugars of the kind in DNA.
"Of course," Breslow says, "showing that it could have happened this way is not the same as showing that it did." He adds: "An implication from this work is that elsewhere in the universe there could be life forms based on D-amino acids and L-sugars. Such life forms could well be advanced versions of dinosaurs, if mammals did not have the good fortune to have the dinosaurs wiped out by an asteroidal collision, as on Earth. We would be better off not meeting them."
The author acknowledges funding from the National Science Foundation.
Reference: "Evidence for the Likely Origin of Homochirality in Amino Acids, Sugars, and Nucleosides on Prebiotic Earth" - Journal of the American Chemical Society
of size relativity. There are many reasons to start thinking about throughout ages "growing up" volume of matter particles, making influence to basic physics too. The dinosaurs are found to be the same specie family, as the birds are, others are connected to lizards. In a way of thinking about existence of slow change of matter volume over ages, we can think about these giants as about common size animals, whose skeletal - stone remains grew up over time because of slow change of physical matter parameters. In this theory of size relativity you can think about all the evolution in different way, and there is not needed any major planetary disaster to make species extinct or disappear. All the changes could be make by the evolution change going along both climate and socialization of herbivore species and their change to carnivorous species. These Rexes and similar purely carnivorous predators could just had have new rivals at their field of predators, who came up from herbivore species with different type of teeth, giving them huge advance in crushing even bones of hunted animals, so they became much more effective in usage of potential energy given by dead animal. T-Rex was able to eat only meat, these new types who came from his "peaceful brothers", most probably during cold times, when there were no plants, were able to crush also bones and became high effective. T-Rex became hunted specie instead of hunter and you can find his "family" only in the smallest relics in the lizard family. These dinosaurs had 2 possibilities - to hide themselves in the trees, so they became birds, or to sneak into lower dense forest and hidden places - to became or remain lizards. The others became herbivores living in water (hippos, elephants, crocodiles) or big and strong or fast enough (rhinoceros, ostriches) or socialized themselves in huge groups (antelopes, horses, zebras, giraffes) - all these species came directly from herbivorous dinosaurs, from which came also carnivorous predators - cat-like species and dog-like species. These have same root - herbivorous dinosaurs - who for a) stayed herbivorous or b) became carnivorous and started hunts of carnivorous dinosaurs like T-Rex. This is only possible - though - with acceptance of the matter-size relativity theory. There are lots of indirect proofs and indications, and hopefully this topic comes to talk sooner or later, because it keeps potential to rewrite completely known history of life on the planet, both plants and animal history.