We know today from fossil specimens that not all dinosaurs were giants, some were as small as a chicken. But there were also giants in the land of the dinosaurs. These giants, many of them very massive, can be seen in a natural history museum near you. Pittsburgh's Carnegie Museum of Natural History has an excellent collection of dinosaur fossils such as Diplodocus carnegii (affectionately named "Dippy' by the public), Apatosaurus louisae, and Tyrannosaurus rex, and many more.
Some of the most massive dinosaurs were the sauropods. They were giant herbivore dinosaurs with long necks, four column-like legs and a long tail (some had whip-like tails). But how did these dinosaurs get so big? One possibility was vegetation was more plentiful. Another possibility oxygen levels and air pressure was higher than they are now. Scientists discovered in amber (fossilized tree sap) high oxygen levels within the amber.
The climate played a large part why dinosaurs were able to grow so big. The climate before the worldwide Flood (Genesis 6-9) was tropical. A provocative recent discovery may provide additional insight as to the cause of the disappearance of the dinosaurs. One major short-term effect was a rapid cooling after the Flood, caused by volcanic air pollution which kept warming sunlight from reaching the earth for a number of years. Recent discovery of palm trees under the ice in Antarctica proves that it once had a tropical climate.
"Whatever triggered this decline (in worldwide temperature at some earlier time) may also be a factor in the extinction of the dinosaurs (which were probably adapted to a tropical climate) and put a premium on the warm-blooded birds and mammals, which can maintain a constant internal temperature" (Asimov's New Guide to Science, (1984), p.204).
The Bible describes a giant creature called "behemoth" which could possibly be a dinosaur (Job 40:15-24). In 1841, Sir Richard Owen coined the word "dinosaur", meaning "terrible lizard", after discovering large reptilian-like fossils. However in the Book of Job, written 4,000 years earlier, God describes behemoth as the largest of all land creatures. It was a plant-eater (herbivore), with great strength in its hips and legs, powerful stomach muscles, a tail that moved like a cedar tree in the wind, and bones like bars of iron. This is an accurate description of sauropods, the largest known dinosaur family.
These giants that were in the land before they went extinct, were truly awesome animals that ever walked planet Earth. I give God the glory and honor for creating these magnificent dinosaurs.
"Thou art worthy, O Lord, to receive glory and honour and power: for thou hast created all things, and for thy pleasure they are and were created" (Revelation 4:11)(KJV).