There's all kinds of info on life in the dinosaur era and ice ages, but what life was there 10-40 mil yrs ago?
399368
I just had to do a poster for my historic geology class.\n50 mya= Earliest whales, molluscs cover from mass extinction\n40 mya= Tropical forests at high latitudes, Arboreal browing animals dominant, earliest bats, peak of warming.\n35 mya= Excticion of rummulitids and other warm-water marien life, resuption of arc volcanism, Climatic deterioration, early Antarctic glaciation.\n30 mya= Forests break up due to cooling and drying\n25 mya= Giant Hornless Rhinoceros predominant, San Andreas Fault created, beginning of Tejas Sequence of ocean fluctuations.\n20 mya= Grassy savannahs monnon in mid latitudes, Antarctic glaciers return.\n15 mya= Mastodonts escape Africa, Diversification of fast-running grazing mammals, Cascaade Arc Basin and Range extension created.\n10 mya= Steppes Replace Savannas, Arctic icecap created.\n5 mya= Extinction of many savannah mammals.\n4 mya= Extinction of large mammals at end of plesitocene.  Mediterranean dries up.
77663
Adapted from Dinosaurs: The Very Latest Information and Hands-On Activities From the Museum of the Rockies, by Liza Charlesworth and Bonnie Sachatello-Sawyer. A Scholastic Professional Book.\n\nWay back in 1676, Robert Plot, the curator of an English museum, described and drew a thigh bone that he believed belonged to a giant man. Although that fossil disappeared without a trace, the surviving illustration suggests that it may well have been part of a "Megalosaurus." Later, in 1822, large teeth discovered in England by Mary Ann Mantell and her husband, Gideon, were thought to be the remains of a huge and extinct iguana. It wasn't until 1841 that British scientist Richard Owen came to realize that such fossils were distinct from the teeth or bones of any living creature. The ancient animals were so different, in fact, that they deserved their own name. So Owen dubbed the group "Dinosauria," which means "terrible lizards."\n\nAcross the ocean in North America, dinosaur tracks were studied in the Connecticut Valley, beginning in the 1830's. They were believed to belong to enormous ravens, freed from Noah's Ark after the Great Flood. At that time, paleontology was long on deduction and short on evidence. This was remedied when two wealthy and competitive American scientists, Othniel Marsh and Edward Cope, raced to excavate fossils in the Rocky Mountain region. In the late 1800's, their separate teams, armed against Native Americans and each other, dug up tons of bones from several sites. All in all, Marsh and Cope's rivalry — known as the Bone Wars — uncovered 136 new species. And their respective fossil displays generated excitement for dinosaurs the world over.\n\nIn the 1900's, enthusiasm for dinosaurs grew steadily, attracting the attention of the scientific community. Institutions such as the Carnegie Museum of Natural History and the American Museum of Natural History assembled dig teams, which uncovered many rich bone beds in North America (as did their counterparts overseas). New sites in Utah revealed several different species, including "Camarasaurus," "Apatosaurus," and "Stegosaurus;" "Tyrannosaurus rex" remains were found in Montana and baby Coelosaurs in New Mexico.\n\nIn recent decades, dinosaur research continues, but the emphasis has shifted from finding and classifying these animals to analyzing and reconstructing their lives and habitats. In the late 1960's, Robert Bakker proposed that these ancient creatures may well have been as agile and energetic as warm-blooded animals. In the mid 1970's, Peter Dodson, along with James Farlow, hypothesized that they used their horns to attract the attention of females, as well as for fighting. And in the late 1970's, Jack Horner made history by identifying some of the first dinosaurs nests and eggs in North America. These important "Maiasaura" fossils helped to determine that some species nested in colonies and cared for their young.\n\nIn the past few years, several paleontologists, including Ken Carpenter, Phil Currie, and William Coombs, have identified juvenile dinosaurs that were previously thought to be adults; and David Weishampel has theorized that some dinosaurs probably used their crests and nasal passages to create sound. Each day, scientists working all over the world, in the field and in research labs, help to redefine the meaning of the world "dinosaur."
380528
Dinosaurs were vertebrate animals that dominated the terrestrial ecosystem for over 160 million years, first appearing approximately 230 million years ago. At the end of the Cretaceous period 65 million years ago, dinosaurs suffered a catastrophic extinction, which ended their dominance on land. Modern birds are considered to be the direct descendants of theropod dinosaurs.
531946
wow that was soooooo long ago,you must be really old.number one was the first t rex went extinct. sorry lol
704239
No, the Earth is much much older.  This is why the Bible is not to be taken literally.  If anything, we were meant to eventually point out these inconsistencies.  The truth is that the dinosaurs existed a long time ago (dragons) and were created to be just another amazing addition to life here on Earth.\n\nThe dinosaurs existed at a time when gravity as we experience it now was attenuated, and we experience much muss less of it.  This is how dinosaurs like the ultrasaur and massive bids like the teratorn were able to walk and fly around without collapsing under their own weight.
33842
I have an MS in paleoclimatology, and I have to say that it is one of the most fascinating topics Ive ever delved into.  It's also amusing to see non-scientist's responses here and on other message boards!\n\nIf you wanted to ask a scientist, you would have to define what you mean when you say "ice age."  There are varying degrees of "ice ages."  For brevity sake, I will assume you mean the relatively cold periods that last approximately 100,000 years that have dominated global climate for the last 2 million years.  Contrary to popular belief, there are periods during the "ice ages" that are almost as warm as today.\n\nBased on paleoclimate evidence that suggest the ice ages have come and gone at least six times in the last 2 million years, the probability is that it will occur again.\n\nThe difficult and possibly dramatic question is: when?  Seeing as though the last "ice age" generally ended about 12,000 years ago (this is debatable, since there is no one date where everywhere across the globe it suddenly became warm), and the average interglacial is 10,000 years, we are overdue.\n\nConsider the widely accepted hypothesis that "global warming"--whether it be natural, human-induced, or a combination--can ultimately (Ill spare you the details) lead to an ice age.  Melting polar sea ice, indicator species dying off in the tropics, large disintigrations of ice shelves in the Antarctic, estimations that global sea level may rise 4 inches in the next 100 years, "wild" weather in many parts of the US...  are these all tell-tale signs that we have already begun down the road to the next glacial period?!?!?\n\nNew-ish data suggest that past climates have changed rapidly--like someone else mentioned either in this thread or another similar one--several degrees Celsius in a matter of decades or less!  The great ice sheets that once reached as far south as Long Island and Iowa wont reappear for tens of thousands of years, but it could get chilly across much of the country real quick!  And possibly as soon as 2020!
507473
Try www.google.com you ll find many sites on the prehistoric time of reptiles
193097
Wow, I'm truly speechless. What people? And if there were people in the Silurian period, why would they travel any differently than people do now?
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It is a huge question, but in general you would want to check paleoclimatology (for example, glaciation of Antarctica after opening of Drake and Tasmania passages), paleontology/biogeography (distribution of fossils and ancient migration of various animal groups).\n\nThere is a page with lecture notes which is very shorthand but touches on most things you may want to check:\nhttp://jersey.uoregon.edu/~mstrick/RogueComCollege/RCC_Lectures/ConDrift_PlateTec.html\n\nAnother link that touches on the subject:\nhttp://pgap.uchicago.edu/PGAP2000-1.html
247560
It depend if you are a religions person or believe in facts. Me, as a geologist I believe in facts and science.\nThe earth forms 4.6 billions years ago. How did we know? By using the radioactive decay method. \nNobody really knows how it form but you can get differrent references. Try historical geology books. \nEarth solidifies around 3 billion years ago, how? From the dated rocks namely Banded Iron Deposits. Life began at PreCambrain era. Meaning 512 millions years ago. Dinosaurs came to life at least 100 million years ago and died 65 miilion years ago because of  a comet hitting the earth.\nActually there are a lot more happend but for your satisfaction try to look for a Historical geology book. A very interesting book.
1098613
Try reading the article on bone from Wikipedia:\nhttp://en.wikipedia.org/wiki/Bone\n\nAnother interesting article is the Scientific American, July 2005, article on "How Dinosaurs Grew So Large--and So Small"\nhttp://www.sciamdigital.com/index.cfm?fa=Products.ViewIssuePreview&ARTICLEID_CHAR=6745BB5C-2B35-221B-6C30EAA4A975E3E3\n(See your school library for a copy)
85861
~4.5 Billion years old.
937907
Approximately 5,000,000,000 years
1127519
http://www.bibleandscience.com/science/dinosaurs.htm explains everything.
161036
Here is one of the most detailed ones available on the internet from the Geological Society of America:\nhttp://www.geosociety.org/science/timescale/timescl.pdf\n\nUSGS has some interesting versions that are put in scale relative to time, so they show dramatically how much longer previous Eons were in comparison to recent Eras:\nhttp://geology.wr.usgs.gov/docs/parks/gtime/gtime2.html\n\nHere is the UC Berkeley Geological Time Machine:\nhttp://www.ucmp.berkeley.edu/help/timeform.html\n\nFinally, if you want to see the coolest images of paleogeography on the net check out Dr Blakey's website at Northern Arizona University:\nhttp://jan.ucc.nau.edu/~rcb7/nam.html\nor at:\nhttp://jan.ucc.nau.edu/~rcb7/
897604
Tertiary, plaeocene to eocene (about 50 million years ago).\n\nOnly minor collisions occured earlier in the Cretaceous.
610011
5,000,000,000 years, more or less