{"id":283647,"date":"2009-03-11T00:00:00","date_gmt":"2009-03-11T07:00:00","guid":{"rendered":"https:\/\/sdnews.com\/discoveries-rekindle-theories-on-areas-prehistoric-climate-mammoths-diet\/"},"modified":"2009-03-11T00:00:00","modified_gmt":"2009-03-11T07:00:00","slug":"discoveries-rekindle-theories-on-areas-prehistoric-climate-mammoths-diet","status":"publish","type":"post","link":"https:\/\/test.sdnews.com\/es\/discoveries-rekindle-theories-on-areas-prehistoric-climate-mammoths-diet\/","title":{"rendered":"Discoveries rekindle theories on area\u2019s prehistoric climate, mammoth\u2019s diet"},"content":{"rendered":"<p>Before you start pointing fingers, heed us: We\u2019re well aware that modern elephants are child\u2019s play compared with the mammoths, their colossal and very distant relatives. We also know that fish aren\u2019t members of the whale family, as they breathe through gills, not nostrils and lungs. The recent Downtown discoveries from prehistory are profound indeed, and for your protection, we thought we\u2019d better choose the words in our headline carefully (here at Downtown News, we\u2019ve always got your back). But the monster is a real element in last month\u2019s East Village excavations of two sets of remains \u2014 those of a Columbian mammoth (a genus that went extinct during the last Ice Age) and a prehistoric baleen whale, possibly a California gray. The monster takes the form of several land-mass and climate shifts that have claimed boatloads of creatures over eons; the latest finds date anywhere from 500- to 600,000 years ago and were discovered during construction work on the new Thomas Jefferson School of Law building at 11th and Island avenues. The mammoth bones, including the skull with right and left upper molars, both tusks, the right lower molar and probably the left, were unearthed recentlyt under about 20 feet of ground. The whale remains, which include several ribs and the lower jaw, were found Feb. 26. This week, fossil experts unearthed the degraded vertebra and tooth and skull fragments of a giant sloth at the same site. The bones were taken to the San Diego Natural History Museum in Balboa Park for further study and perhaps for an exhibition some months down the line. The discovery of animal fossils isn\u2019t big news around here, at least in the county\u2019s northern portion. The land under Carlsbad and Oceanside is the site of many such discoveries, notably a set of giant mastodon bones found in the summer of 2007; the present-day Anza-Borrego Desert apparently had mammoths and even camels in it until about 300,000 years ago. But two things excite natural history museum paleontologist Tom Demere about the current mystery: The whale find is a first for San Diego County, and those bones were buried only 10 to 15 feet deeper than the mammoth\u2019s. &#8220;This is just a hypothesis,&#8221; Demere said, &#8220;but the animals were separated by about a hundred-thousand years in time. The whale was living here during a period of global warming and a high sea level (about 600,000 years ago). The mammoth was living here (100,000 years later) during a period of global cooling and lower sea level. In looking at that, we have this interesting pattern of sea-level change that I would correlate with the global pattern of sea-level change for portions of the last couple hundred-thousand years.&#8221; Moreover, Demere said, the mammoth was sandwiched between the whale and a bed of seashells, fueling his speculation about the link between atmospheric changes and life on Earth. &#8220;We\u2019re still working out what this means,&#8221; Demere continued, &#8220;which is part of the excitement.&#8221; Meanwhile, if you\u2019ve lived in San Diego any length of time at all \u2014 and you probably have \u2014 you know that the greenery around here is a freak of human nature. We basically live in a borderline arid climate, you and I, as our annual precipitation total (less than 12 inches) approaches the conventional figure used in defining desert conditions (10 or fewer inches\u2019 precip a year). The water here also tends to evaporate quickly, as the sun shines (at least in part) about 260 out of 365 days. But a half-million years ago, Demere explained, &#8220;We probably had a climate more like Northern California. Rainfall would have been different. It would have been higher in the periods of global cooling,&#8221; spawning lush, woody, grassy vegetation that the local landscape architects of today can only dream about. That\u2019s the kind of menu on which the mammoths survived for millennia upon millennia. But Demere is quick to point out that the animals survived much drier eras, dying out only about 12,500 years ago. &#8220;The puzzling question,&#8221; Demere said, &#8220;is why aren\u2019t they still here. If they survived these other periods, what happened?&#8221; The recipe, he suggested, might have involved a &#8220;perfect storm,&#8221; of sorts \u2014 climatic changes, an extraterrestrial catalyst such as a comet or meteor and, of course, man and his predatory instincts. Human beings had made it to North America by that time, Demere noted. And you know what that means. It means that, many centuries down the road, they\u2019d devise a bunch of sophisticated devices to encase the remains of very large animals during excavation. The Columbian mammoth stood as high as 14 feet at the shoulder and weighed as much as 10 tons, while the baleen whale\u2019s jaw alone measured eight feet \u2014 but as Demere explained, &#8220;If you tried to pick these up, they\u2019d just crumble. We have to dig around the remains so they\u2019re on a pedestal of sediment&#8221; and create a plaster &#8220;bandage&#8221; to stabilize the remains. That pedestal is crushingly heavy too \u2014 one false move, and it could conceivably implode on the unsuspecting skeleton. But that didn\u2019t happen this time. The bones were safely transported to the natural history museum and its warehouse in National City, their secrets safely in tow. This discovery alone fueled unusually robust theories about life around here just shortly before you were born \u2014 with its upshot, the best is yet to come.<\/p>","protected":false},"excerpt":{"rendered":"<p>Before you start pointing fingers, heed us: We\u2019re well aware that modern elephants are child\u2019s play compared with the mammoths, their colossal and very distant relatives. We also know that fish aren\u2019t members of the whale family, as they breathe through gills, not nostrils and lungs. The recent Downtown discoveries from prehistory are profound indeed, [&hellip;]<\/p>","protected":false},"author":726,"featured_media":283648,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_seopress_robots_primary_cat":"11561","_seopress_titles_title":"Discoveries rekindle theories on area\u2019s prehistoric climate, mammoth\u2019s diet","_seopress_titles_desc":"","_seopress_robots_index":"","jnews-multi-image_gallery":[],"jnews_single_post":[],"jnews_primary_category":[],"jnews_social_meta":[],"jnews_override_counter":[],"footnotes":""},"categories":[11551,11561],"tags":[],"class_list":["post-283647","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-news","category-peninsula-beacon"],"_links":{"self":[{"href":"https:\/\/test.sdnews.com\/es\/wp-json\/wp\/v2\/posts\/283647","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/test.sdnews.com\/es\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/test.sdnews.com\/es\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/test.sdnews.com\/es\/wp-json\/wp\/v2\/users\/726"}],"replies":[{"embeddable":true,"href":"https:\/\/test.sdnews.com\/es\/wp-json\/wp\/v2\/comments?post=283647"}],"version-history":[{"count":0,"href":"https:\/\/test.sdnews.com\/es\/wp-json\/wp\/v2\/posts\/283647\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/test.sdnews.com\/es\/wp-json\/wp\/v2\/media\/283648"}],"wp:attachment":[{"href":"https:\/\/test.sdnews.com\/es\/wp-json\/wp\/v2\/media?parent=283647"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/test.sdnews.com\/es\/wp-json\/wp\/v2\/categories?post=283647"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/test.sdnews.com\/es\/wp-json\/wp\/v2\/tags?post=283647"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}