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  • Whale Shark Aggregation in Belize – Cristiana & Alain Bontemps (2009)

    Whale Shark Aggregation in Belize – Cristiana & Alain Bontemps (2009)

    External fertilization is a wasteful process but still enables survival of many aquatic species. For external fertilization to be successful certain prerequisites are needed: high population numbers, aggregation of these large groups and synchronous release of gametes. Animals are great resource maximizers. Once they discover a high value resource they will exploit it as efficiently as possible. Gametes (sperms and eggs) released during external fertilization of large groups of fish such as the Jack are extremely nutritious for filter feeders […]

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  • Rapid Worker Recruitment in Aphaenogaster Ants

    Rapid Worker Recruitment in Aphaenogaster Ants

    In this short observation a single worker drags a yellow jacket wasp (Vespula spp.) until a point close to the nest and then switches to a different task. She leaves to recruit more workers as a scout. Until the first recruits arrive two other workers tend the prey. The location of the prey must have been close to the nest because a third worker joins them 55 seconds after the scout leaves. Based on the time stamp of the unedited […]

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  • Spider Mom – Alvaro Mendoza (2012)

    Spider Mom – Alvaro Mendoza (2012)

    Egg laying by a female spider filmed by Alvaro Mendoza. Highly choreographed light use makes this short observation particularly striking. Spiders reproduce sexually. Fertilization is internal but the sperm is not inserted into the female’s body by the male’s genitals. Unlike many land-living arthropods, male spiders do not produce ready-made spermatophores (packages of sperm). Males spin small sperm webs on to which they ejaculate and then transfer the sperm to syringe-like structures on the tips of their pedipalps. Image source: […]

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  • Crippled Cranefly Orchid (Tipularia discolor) (2014)

    Crippled Cranefly Orchid (Tipularia discolor) (2014)

    Crippled Cranefly Orchid (Tipularia discolor). Recorded on August 9th 2014, Georgia State Botanical Garden, Athens, GA, USA. The genus Tipularia has three species. Crippled cranefly orchid (Tipularia discolor) is the only species found in North America. The other two species are Asian found in the Himalayas and Japan. Tipularia discolor grows in organic humus-rich soils of closed canopy oak-pine forests in the Eastern United States. It is protected as Threatened, Endangered, or Rare in Florida, Massachusetts, Michigan, New York, Pennsylvania. […]

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  • The Antikythera Mechanism: The Two-Thousand-Year-Old Computer – Mike Beckham (2012)

    The Antikythera Mechanism: The Two-Thousand-Year-Old Computer – Mike Beckham (2012)

    Antikythera Mechanism is one of the best demonstrations of human intellect attempting to understand nature systematically. The contraption is most certainly a very complex device. It is an impressively accurate “analog model” of our then earth-centric universe. Science gives us prediction power and Antikythera Mechanism is an excellent example for how astronomical observations can be defined mathematically to reconcile lunar and solar calendars and predict eclipses with hourly accuracy using 27 gear pieces. It uses the Metonic Cyle first implemented […]

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  • How Chameleons Change Color? (2015)

    How Chameleons Change Color? (2015)

    Long projectile tongue, independently movable eyes and rapid color change. Chameleons are indeed very interesting animals (see the detailed account of Aristotle at the bottom of this post). Main video is a concatenation of all five supplementary materials associated with the a study demonstrating color change in Chameleons. You can view them individually below. The following video by The Economist makes a successful summary based on the same material: Reproductively mature chameleon males rapidly switch on bold threatening colors when […]

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  • Crossection of a Dandelion Compound Flower – Rüdiger Hartmann (2015)

    Crossection of a Dandelion Compound Flower – Rüdiger Hartmann (2015)

    Dandelion (Taraxacum officinale) is one of the most ubiquitous plants belonging to the family Asteraceae. The plant is native to Eurasia but has become naturalized to all temperate regions of the World introduced unintentionally by Humans. It’s compound flowers are self-pollinated and seeds are wind dispersed. In this short observation developmental biologist Dr. Rüdiger Hartmann of the University of Freiburg has done a wonderful job of showing the dynamics of the mature compound flowers (inflorescence) using timelapse videography in his […]

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  • The Origin of Birds – Dan Lewitt – HHMI (2015)

    The Origin of Birds – Dan Lewitt – HHMI (2015)

    The Great Transitions is a three part documentary covering evolutionary origins of land vertebrates tetrapods, birds and Humans. In this second installment of the series, paleontologist Julia Clarke tells how birds evolved from dinosaurs. When the first Archaeopteryx fossil was discovered in a quarry in Germany in the early 1860s it created a lot of excitement. The discovery came only a few years after the publication of the Origin of Species by Charles Darwin. Since then dozens of Archeopteryx fossils […]

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