The Oligocene (symbol O_G^[1]) is a geologic epoch of the Paleogene Period and extends from about 34 million to 23 million years before the present (33.9±0.1 to 23.03±0.05 Ma). As with other older geologic periods, the rock beds that define the period are well identified but the exact dates of the start and end of the period are slightly uncertain. The name Oligocene comes from the Greek ὀλίγος (oligos, few) and καινός (kainos, new), and refers to the sparsity of additional modern mammalian species of fauna after a burst of evolution during the Eocene. The Oligocene follows the Eocene Epoch and is followed by the Miocene Epoch. The Oligocene is the third and final epoch of the Paleogene Period.

The Oligocene is often considered an important time of transition, a link between the archaic world of the tropical Eocene and the more modern ecosystems of the Miocene.^[2] Major changes during the Oligocene included a global expansion of grasslands, and a regression of tropical broad leaf forests to the equatorial belt.

The start of the Oligocene is marked by a notable extinction event; the replacement of European fauna with Asian fauna, except for the endemic rodent and marsupial families called the Grande Coupure. The Oligocene-Miocene boundary is not set at an easily identified worldwide event but rather at regional boundaries between the warmer late Oligocene and the relatively cooler Miocene.

Subdivisions[link]

Oligocene faunal stages from youngest to oldest are:

Climate[link]

The Paleogene Period general temperature decline is interrupted by an Oligocene 7 million year stepwise climate change. A deeper 8.2 °C, 400,000 year temperature depression leads the 2 °C, 7 million year stepwise climate change 33.5 Ma (Million years ago).^[3][4] The stepwise climate change began 25.5Ma and lasted through 32.5 Ma, as depicted in the PaleoTemps chart. The Oligocene climate change was a global ^[5] increase in ice volume and a 55 M (181 feet) decrease in sea level (35.7-33.5 Ma) with a closely related (25.5-32.5 Ma) temperature depression.^[6] The 7 million year depression abruptly terminated within 1-2 million years of the La Garita Caldera eruption at 28-26 Ma. A deep 400,000 year glaciated Oligocene Miocene boundary event is recorded at McMurdo Sound and King George Island.

Paleogeography[link]

During this period, the continents continued to drift toward their present positions. Antarctica became more isolated and finally developed an ice cap.(Haines)

Mountain building in western North America continued, and the Alps started to rise in Europe as the African plate continued to push north into the Eurasian plate, isolating the remnants of the Tethys Sea. A brief marine incursion marks the early Oligocene in Europe. Marine fossils from the Oligocene are rare in North America. There appears to have been a land bridge in the early Oligocene between North America and Europe, since the faunas of the two regions are very similar. Sometime during the Oligocene, South America was finally detached from Antarctica and drifted north towards North America. It also allowed the Antarctic Circumpolar Current to flow, rapidly cooling the Antarctic continent.

Flora[link]

Angiosperms continued their expansion throughout the world as tropical and sub-tropical forests were replaced by temperate deciduous forests. Open plains and deserts became more common and grasses expanded from their water-bank habitat in the Eocene moving out into open tracts. However, even at the end of the period grass was not quite common enough for modern savannas.(Haines)

In North America, subtropical species dominated with cashews and lychee trees present, and temperate trees such as roses,^{[clarification needed]} beeches, and pines were common. The legumes spread, while sedges, bulrushes, and ferns continued their ascent.

Fauna[link]

Restoration of oligocene fauna of North America, by Jay Matternes

Important Oligocene land fauna are found on all continents at this time. Even more open landscapes allowed animals to grow to larger sizes than they had earlier in the Paleogene. Marine faunas became fairly modern, as did terrestrial vertebrate fauna on the northern continents. This was probably more as a result of older forms dying out than as a result of more modern forms evolving. Many groups, such as horses, entelodonts, rhinoceroses, oreodonts, and camels, became more able to run during this time, adapting to the plains that were spreading as the Eocene rainforests receded.

South America was isolated from the other continents and evolved a quite distinct fauna during the Oligocene. The South American continent became home to strange animals such as pyrotheres and astrapotheres, as well as litopterns and notoungulates. Sebecosuchian crocodiles, terror birds, and carnivorous marsupials, like the borhyaenids remained the dominant predators. Brontotheres died out in the Earliest Oligocene, and creodonts died out outside Africa and the Middle East at the end of the period. Multituberculates, an ancient lineage of primitive mammals, also went extinct in the Oligocene. The Oligocene was home to a wide variety of strange mammals. A good example of this would be in the White River Badlands of the United States, which were formerly a semi-arid prairie home to many different types of endemic mammals, including entelodonts like Archaeotherium, camels (such as Poebrotherium), running rhinos, three-toed horses (such as Mesohippus), nimravids, protoceratids, and early dogs like Hesperocyon. Oreodonts, an endemic American group, were very diverse during this time. In Asia during the Oligocene, a group of running rhinos gave rise to the indricotheres, like Indricotherium, which were the largest land mammals ever to walk the Earth.

The marine animals of Oligocene oceans resembled today's fauna, such as the bivalves. The fossil record of marine mammals is a little spotty during this time, and not as well known as the Eocene or Miocene, but some fossils have been found. The baleen and toothed cetaceans, or whales, had just appeared, and their ancestors, the archaeocete cetaceans began to decrease in diversity due to their lack of echolocation, which was very useful as the water became colder and cloudier. Other factors to their decline could include climate changes and competition with today's modern cetaceans and the carcharhinid sharks, which also appeared in this epoch. Early desmostylians, like Behemotops, are known from the Oligocene. Pinnipeds probably appeared near the end of the epoch from a bear-like or otter-like ancestor.

Oceans[link]

The Oligocene sees the beginnings of modern ocean circulation, with tectonic shifts causing the opening and closing of ocean gateways. Cooling of the oceans had already commenced by the Eocene/Oligocene boundary,^[7] and they continued to cool as the Oligocene progressed. The formation of permanent Antarctic ice sheets during the early Oligocene and possible glacial activity in the Arctic may have influenced this oceanic cooling, though the extent of this influence is still a matter of some significant dispute.

The Effects of Oceanic Gateways on Circulation[link]

The opening and closing of ocean gateways: the opening of the Drake Passage; the opening of the Tasmanian Gateway and the closing of the Tethys seaway; along with the final formation of the Greenland-Iceland-Faroes sill; played vital parts in reshaping oceanic currents during the Oligocene. As the continents shifted to a more modern configuration, so too did ocean circulation.^[8]

The Drake Passage[link]

The Drake Passage is located between South America and Antarctica. Once the Tasmanian Gateway between Australia and Antarctica opened, all that kept the Southern Ocean from being completely isolated was the connection of South America to Antarctica. As the South American continent moved north the Drake Passage opened and enabled the formation of the Antarctic Circumpolar Current (ACC), which would have kept the cold waters of Antarctica circulating around that continent and strengthened the formation of Antarctic Bottom Water (ABW).^[8][9] With the cold water concentrated around Antarctica, sea surface temperatures and, consequently, continental temperatures would have dropped. The onset of Antarctic glaciation occurred during the early Oligocene,^[10] and the effect of the Drake Passage opening on this glaciation has been the subject of much research. However, some controversy still exists as to the exact timing of the passage opening, whether it occurred at the start of the Oligocene or nearer the end. Even so, many theories agree that at the Eocene/Oligocene (E/O) boundary, a yet shallow flow existed between South America and Antarctica, permitting the start of an Antarctic Circumpolar Current.^[11]

Stemming from the issue of when the opening of the Drake Passage took place, is the dispute over how great of an influence the opening of the Drake Passage had on the global climate. While early researchers concluded that the advent of the ACC was highly important, perhaps even the trigger, for Antarctic glaciation^[8] and subsequent global cooling, other studies have suggested that the δO¹⁸ signature is too strong for glaciation to be the main trigger for cooling.^[11] Through study of Pacific ocean sediments, other researchers have shown that the transition from warm Eocene ocean temperatures to cool Oligocene ocean temperatures took only 300,000 years,^[7] which strongly implies that feedbacks and factors other than the ACC were integral to the rapid cooling.^[7]

The Late Oligocene Opening of the Drake Passage[link]

The latest-hypothesized time for the opening of the Drake Passage is during the early Miocene.^[7] Despite the shallow flow between South America and Antarctica, there was not enough of a deep water opening to allow for significant flow to create a true Antarctica Circumpolar Current. If the opening occurred as late as hypothesized, then the Antarctica Circumpolar Curren could not have had much of an effect on early Oligocene cooling, as it would not have existed.

The Early Oligocene Opening of the Drake Passage[link]

The earliest-hypothesized time for the opening of the Drake Passage is around 30 Ma.^[7] One of the possible issues with this timing was the continental debris, as it were, cluttering up the seaway between the two plates in question. This debris, along with what is known as the Shackleton Fracture Zone, has been shown in a recent study to be fairly young, only about 8 million years old.^[9] The aforementioned study concludes that the Drake Passage would be free to allow significant deep water flow by around 31 Ma. This would have facilitated an earlier onset of the Antarctic Circumpolar Current.

Currently, an opening of the Drake Passage during the early Oligocene is favored.

The Opening of the Tasman Gateway[link]

The other major oceanic gateway opening during this time was the Tasman, or Tasmanian, depending on the paper, gateway between Australia and Antarctica. The time frame for this opening is less disputed than the Drake Passage and is largely considered to have occurred around 34 Ma. As the gateway widened, the Antarctic Circumpolar Current strengthened.

The Tethys Seaway Closing[link]

Though the Tethys was not a gateway, but rather a sea in its own right. Its closing during the Oligocene had significant impact on both ocean circulation and climate. The collisions of the African plate with the European plate and of the Indian subcontinent with the Asian plate, cut off the Tethys seaway that had provided a low-latitude ocean circulation.^[12] The closure of Tethys built some new mountains (the Zagros range) and drew down more carbon dioxide from the atmosphere, contributing to global cooling.^[13]

Greenland-Iceland-Faroes[link]

The gradual separation of the clump of continental crust and the deepening of tectonic sill in the North Atlantic that would become Greenland, Iceland, and the Faroe Islands helped to increase the deep water flow in that area.^[10] More information about the evolution of North Atlantic Deep Water will be given a few sections down.

Ocean Cooling[link]

Evidence for ocean-wide cooling during the Oligocene exists mostly in isotopic proxies. Patterns of extinction^[14] and patterns of species migration^[15] can also be studied to gain insight into ocean conditions. For a while, it was thought that the glaciation of Antarctica may have significantly contributed to the cooling of the ocean, however, recent evidence tends to deny this.^[9][16]

Deep Water[link]

Isotopic evidence suggests that during the early Oligocene, the main source of deep water was the North Pacific and the Southern Ocean. As the Greenland-Iceland-Faroe sill deepened and thereby connected the Norwegian-Greenland sea with the Atlantic Ocean, the deep water of the North Atlantic began to come into play as well. Computer models suggest that once this occurred, a more modern in appearance thermo-haline circulation started.^[12]

North Atlantic Deep Water[link]

Evidence for the early Oligocene onset of chilled North Atlantic Deep Water lies in the beginnings of sediment drift deposition in the North Atlantic, such as the Feni and Southeast Faroe drifts^[10]

South Ocean Deep Water[link]

The chilling of the South Ocean Deep Water began in earnest once the Tasmanian Gateway and the Drake Passage opened fully.^[9] Regardless of the time at which the opening of the Drake Passage occurred, the effect on the cooling of the Southern Ocean would have been the same.

Impact events[link]

Recorded extraterrestrial impacts:

• Nunavut, Canada (23 Ma, crater 24 km (15 mi) diameter,)

Supervolcanic explosions[link]

La Garita Caldera (28 through 26 million years ago, VEI=9.2)^[17]

See also[link]

• List of fossil sites (with link directory)
• Turgai Sea

References[link]

• Ogg, Jim; June, 2004, Overview of Global Boundary Stratotype Sections and Points (GSSP's) http://www.stratigraphy.org/gssp.htm Accessed April 30, 2006.

External links[link]

Wikimedia Commons has media related to: Oligocene

• Paleos: Oligocene
• UCMP Berkeley Oligocene Page
• Prehistoric Pictures, in the Public Domain
• Oligocene Leaf Fossils
• Olicgocene Fish Fossils
• PaleoMap Project: Oligocene
• Oligocene Microfossils: 300+ images of Foraminifera

This article appears to be written like an advertisement. Please help improve it by rewriting promotional content from a neutral point of view and removing any inappropriate external links. (May 2011)

Gary Vaynerchuk
Gary Vaynerchuk
Born	(1975-11-14) November 14, 1975 (age 36) Babruysk, U.S.S.R.
Known for	Wine education, wine criticism, social marketing
Notable work(s)	Wine Library TV
Website
garyvaynerchuk.com

Gary Vaynerchuk (born November 14, 1975, in Babruysk, U.S.S.R. [presently Belarus]) is a video blogger, co-owner and director of operations of a wine retail store, and an author and public speaker on the subjects of social media, brand building and e-commerce. Vaynerchuk immigrated to the U.S. in 1978, and after graduating from Mount Ida College in Newton, MA, transformed his father's Springfield, NJ liquor store into a large scale retail wine store named Wine Library,^[1] and in 2006 started the video blog Wine Library TV, a daily internet webcast on the subject of wine, which launched his career of internet celebrity.

Reaction[link]

He has been featured in The Wall Street Journal,^[2] GQ, and Time,^[3] appeared on Late Night with Conan O'Brien and Ellen.^[4] Vaynerchuk has been described as "the first wine guru of the YouTube era",^[5][6] "the wine world's new superstar",^[7] and by Rob Newsom, a Washington State wine maker, "outside of Robert Parker, probably the most influential wine critic in the United States".^[8] In the July 2009 Decanter publication of "The Power List" ranking of the wine industry's individuals of influence, Vaynerchuk placed at number 40, citing that he "represents the power of blogging".^[9][10]

In August 2010 it was announced that Vaynerchuk will host a weekly, two hour call-in radio show titled Wine & Web with Gary Vaynerchuk on the digital radio station Sirius XM.^[11]

[edit] Wine Library TV

New Media Expo 2008

Left: with Justine Ezarik & Leo Laporte  Right: with Ezarik, et al.

Wine Library TV (WLTV or The Thunder Show) (2006–2011) was a video podcast hosted by Vaynerchuk, featuring wine reviews and advice on wine appreciation. Episodes consisted of wine tastings along with other wine related topics. The show debuted on February 21, 2006, and is produced on a daily basis, on weekdays, and is taped in the Wine Library store in Springfield, NJ. Episodes taped Monday through Thursday usually took place on a desk in Vaynerchuk's office, normally tasting three or four wines, and the Friday episode took place on Vaynerchuk's office couch, tasting usually only one wine and answering questions submitted via his Facebook application Ask Gary.^[12] The show may be watched by 90,000 viewers.^[13] Vaynerchuk appeared on the cover of the December 2008 issue of Mutineer Magazine, launching the "Mutineer Interview" series.

After 1,000 episodes of Wine Library TV, the show was retired in March 2011 ^[14], replaced by a very similar video podcast called The Daily Grape, with a slightly shorter format of only two wine reviews, and fewer guests.

Vaynerchuk gives his impressions and finally rates wines using the 100 point scale. As an outspoken critic of numerical scores, he has acknowledged his hypocrisy in using them.^[5][15]

While typically a one man show, on occasion guests have been featured in the program. To date celebrity guests include Jancis Robinson,^[13] Heidi Barrett, George M. Taber, Kevin Rose, Maynard James Keenan, Michael Steinberger, Ingrid Hoffmann, Timothy Ferriss, Jim Cramer of CNBC's Mad Money, Kermit Lynch, Wayne Gretzky, and Dick Vermeil.^[16]

Vaynerchuk has also announced a partnership with Eatdrinkordie.com, where he has released videos about wine, sometimes working with celebrities like Anna Faris.

In March 2009, Wine Library TV was nominated in the Streamy Awards.

August 23rd, 2011 he announced on Daily Grape that he is retiring from wine video blogging. ^[17]

[edit] Crush It

In March 2009, Vaynerchuk signed a 10-book deal with HarperStudio for over $1,000,000 and released the first book, Crush It! Why Now is the Time to Cash in on your Passion, in October 2009. The deal is groundbreaking in the publishing world as one of the first attempts to successfully use a low-advance/high royalty business model.^[18] In the first weeks of its release Crush It climbed to #1 on the Amazon Best Seller list for Web Marketing books. It also opened at #2 on the New York Times bestseller list and #7 on the Wall Street Journal Bestseller List.^[19]

The book encourages people to determine what truly makes them happy and pursue monetizing around it on the internet. It argues that because of recent social and technological trends the cost of producing content has been driven low enough that passion, knowledge, and effort, which the book calls "sweat equity", are now all one needs to build a brand and business.

Crush It was also among the first books released on the Vook platform.^[20]

Vaynerchuk appeared in an episode of the CollegeHumor web series Jake and Amir in 2009, and parodied the slightly nonsensical aspect of Crush It.

Awards and honors[link]

• 2003: Market Watch magazine Business Award: "Market Watch Leader" (youngest recipient ever)
• 2006: People's Choice Vloggie in the categories of "Cooking" and "Instructional/Educational"^[21]
• 2007: American Wine Blog Awards, Best Wine Podcast or Videoblog^[22]
• 2007: The Morning News's "Favorite Web Phenomenon, Soon-to-Be Culinary Celebrity, Web Bucket-Spitter"^[23]
• 2008: Bravo A-List Awards, 2008 Nominee for A-List Celebrity
• 2011: The Wall Street Journal Twitter's Small Business Big Shots ^[24]

Bibliography[link]

• Gary Vaynerchuk's 101 Wines: Guaranteed to Inspire, Delight, and Bring Thunder to Your World (2008)
• Crush It!: Why NOW Is the Time to Cash In on Your Passion (2009)
• The Thank You Economy (2011)

References[link]

External links[link]

• Gary Vaynerchuk official site
• "Daily Grape". http://dailygrape.com/. 
• Wine Library TV
• Vaynermedia.com
• Gary Vaynerchuk talks Food & Wine at Epcot in Walt Disney World with Lou Mongello from WDWRadio
• Gary Vaynerchuk at the Internet Movie Database
• Crush It song official music video