Antarctic bryozoans and Robert Falcon Scott


This video is called Scott of the Antarctic centenary: Retracing his infamous Terra Nova expedition.

From LiveScience:

Antarctic Creature’s Growth Rate Mysteriously Doubles

by Wynne Parry, LiveScience Senior Writer

Date: 22 February 2011 Time: 03:58 PM ET

Small filter-feeding animals that look like branched twigs collected more than a century ago from Antarctica‘s Ross Sea reveal a mysterious increase in how fast the modern-day animals have been growing over the past two decades.

While the researchers can only speculate the cause right now, the amped-up growth makes the tiny organisms carbon collectors, potentially a positive thing for climate change.

Captain Robert Falcon Scott is best known as head of the second expedition to reach the South Pole, and who, with his team, died on the return trip in 1912. But unlike other polar explorers, he also made a variety of high-quality scientific collections, said David Barnes, a researcher with the British Antarctic Survey. [Gallery: Scientists at the Ends of the Earth]

“Now that people are very interested in change in the polar regions, those specimens have become incredibly valuable as the only source of information at that time,” Barnes told LiveScience.com.

These included samples of the tiny animals, a species of bryozoan called Cellarinella nutti, collected with data on the longitude, latitude and depth, Barnes said. Like trees, these creatures produce annual growth rings, giving researchers a window into how growth rates may have changed over time.

Scott’s specimens, along with others, allowed Barnes and his collaborators to compare growth rates for the creatures living on the floor of the Ross Sea from 1890 to 2008.

Like corals, most bryozoans secrete calcium carbonate to form their hard exoskeletons as they grow. The team found that growth rates, or the calcium carbonate each specimen acquired per year, remained roughly constant from 1890 through 1970, although there was a great deal of variability in the 1950s and 1960s. The next available data, from the 1990s to 2008, showed the bryozoans’ growth rates doubled, so the animals were adding twice as much calcium carbonate per year.

The animals are most likely growing because more of their food – marine algae called phytoplankton – is available for longer periods, allowing them to consume — and grow — more, Barnes said. However, it’s not clear why phytoplankton blooms are lasting longer in the Ross Sea, he said.

Redescription of some bryozoan species described by J. Jullien from Iberian waters: here.

The Great White Silence – review of film about Scott: here.

Scott of the Antarctic anniversary to focus on science, not the sideshow: here.

Scott’s own Antarctic expedition photographs published for first time: here.

On August 9, 2011, the Moderate Resolution Imaging Spectroradiometer (MODIS) on the Aqua satellite captured this view of a similar band of brown between the Great Barrier Reef and the Queensland shore. Though it’s impossible to identify the species from satellite imagery, such red-brown streamers are usually trichodesmium. Sailors have long called these brown streamers “sea sawdust.” Trichodesmium, a form of cyanobacteria, are small, usually single-celled organisms that grow in the ocean and produce food through photosynthesis like plants: here.

Scientists recently announced the discovery of a missing evolutionary link — a fossil of the first known member of the modern bryozoans to grow up into a structure: here.

6 thoughts on “Antarctic bryozoans and Robert Falcon Scott

  1. Pingback: British Conservative attack on conservation | Dear Kitty. Some blog

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  3. 10-04-2014 | Exotisch mosdiertje op strand Texel

    Op Texel is onlangs een voor ons land onbekend mosdiertje aangetroffen door een medewerkster van Ecomare. Sytske Dijksen vond op de Hors, de grote zandvlakte aan de zuidwestelijke punt van Texel, een aangespoeld plastic krat. Op het krat bleken zich mosdiertjes gevestigd te hebben. Deze waterdiertjes van hooguit een millimeter groot leven in doosvormige, tot kolonies verkitte kalkskeletten. De naam ‘mosdiertje’is goed gekozen, omdat sommige soorten uiterlijk overeenkomst vertonen met mosjes, die in de stroming heen en weer worden gewiegd. Mosdiertjes geven over het algemeen de voorkeur aan warme, tropische wateren, maar sommige soorten komen ook in onze kustwateren voor.

    Na onderzoek bleek dat Het door Sytske Dijksen aangetroffen exemplaar een voor ons land onbekende soort betrof: Pentapora, een oranjekleurig mosdiertje. Overleden exemplaren verkleuren tot vaalwit.

    Het kalkskelet van Pentapora is opvallend, omdat de skeletjes haaks op de ondergrond staan en daardoor een kantpatroon vormen. Aan de kusten van het Kanaal en Zuid-Engeland komt Pentapora veel voor, maar in Nederland was dit mosdiertje nog nooit eerder aangespoeld. Dankzij het drijvende krat hebben we er nu een nieuwe soort bij.

    Exotische planten en dieren vinden in veel gevallen hun weg naar ons land door menselijk ingrijpen. Ook schaal- en schelpdieren overbruggen vaak enorme afstanden. Een achteloos in zee geworpen plastic krat is al voldoende geweest voor het mosdiertje om de Noordzee over te steken.

    Bron: Ecomare

    Like

  4. Pingback: Australian mining polluted South Pole before Amundsen discovered it | Dear Kitty. Some blog

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  6. Pingback: Antarctic flies protect their eggs with ‘antifreeze’ | Dear Kitty. Some blog

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