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  • An Annotated Animation of Zebrafish Embryo Development – Edwin Mutuma Murungi (2017)

    An Annotated Animation of Zebrafish Embryo Development – Edwin Mutuma Murungi (2017)

    Evolutionarily speaking all of us are tetrapods and contain a fish inside! Take the retention of embryonic gill arches for example, still observed in quite a few people. Preaurucular pit is the scientific term for this ancestral structure. Its presence in Humans reflects the “evo-devo” aspect of our shared biological heritage with all vertebrates living on earth. Here, animated by Edwin Mutuma Murungi, the annotated animation of zebrafish embryo development produced by Norwegian University of Life Sciences – NMBU Learning […]

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  • The Axolotl: A Cut Above The Rest – Science Friday/Christian Baker (2016)

    The Axolotl: A Cut Above The Rest – Science Friday/Christian Baker (2016)

    Tissue regeneration is a fascinating biological subject. Many invertebrate organisms such as crabs, starfishes, sponges, jawless fish such as the lampreys and planarian flatworms can regenerate body parts. Among the vertebrates salamanders, especially the axolotl is a legendary study species for biologists. The axolotl is a highly endangered Mexican salamander with a fascinating ability to regenerate. Curiously, although both are amphibians salamanders can regenerate but frogs cannot. Comparison of such contrasting groups is particularly useful in understanding organ and tissue […]

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  • Identifying the Key Genes for Regeneration | HHMI BioInteractive (2017)

    Identifying the Key Genes for Regeneration | HHMI BioInteractive (2017)

    All multi-cellular organisms have a healing response. Most have the ability to regenerate lost body parts. Plants regenerate in fairly similar ways across diverse families. Animals on the other hand show a remarkable diversity. One can shred a sponge into pieces but the cells can rearrange and organize themselves in a surprisingly rapid manner. Human tissue and organ regeneration is a curious goal for medicine. However in order to achieve this one must understand whether there are common cellular and […]

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  • Becoming: Development of a Salamander Embryo – Jan van IJken (2018)

    Becoming: Development of a Salamander Embryo – Jan van IJken (2018)

    Everyone of us started life from one single cell formed by the fusion of an egg and a sperm. That single cell gave rise to every structure in our bodies. How did that happen? Salamanders especially the axolotl are known to be able to regenerate limbs while frogs and lizards cannot. How and why? The Dutch filmmaker Jan van IJken did a superb job bringing a fresh new artistic look into the fascinating process of vertebrate embryo development. The original […]

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  • The Origin of Species: Lizards in an Evolutionary Tree – Dan Lewitt / HHMI (2013)

    The Origin of Species: Lizards in an Evolutionary Tree – Dan Lewitt / HHMI (2013)

    Anole lizards together with cichlid fishes and Darwin’s finches are one of the star organisms in studying a rapid evolution pattern called adaptive radiation. Jonathan Losos is a veteran field biologist that has studied the traits that enable dozens of anole species to adapt to different niches in the islands of the Caribbean. Differences in limb length, body shape, and toepad size allow different species to be successful on the ground. However on vegetation surfaces such as thin branches, or […]

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  • Galapagos Finch Evolution – Dan Lewitt – HHMI (2013)

    Galapagos Finch Evolution – Dan Lewitt – HHMI (2013)

    The Galapagos is home to many iconic species. Each are unique on their own and form a case study in evolutionary biology. Darwin’s finches and mocking birds with their striking beak morphology provided the first clues to Darwin in formulating the mechanism of evolution by natural selection. The Galapagos was the origin of the Origin of the Species. Finches in the island of Daphne Major have been studied for more than 40 years by Princeton University scientists Peter and Rosemary […]

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  • Backstage in the Wild: Yale Insights into Chimpanzee – David Watts (2012)

    Backstage in the Wild: Yale Insights into Chimpanzee – David Watts (2012)

    This short but densely informative interview is a must-see resource about our closest primate cousins, the chimpanzees. Yale University Anthropologist Dr. David Watts educates us about social interactions and behavior of chimpanzees based on what has been learned from long-term non-Human primate observations. Observation of his and his co-workers at the University of Michigan from the Kibale National Park and Ugandan national park Ngogo formed the basis for feature films such as the Chimpanzee made by the veteran BBC filmmaker […]

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  • The Last Neanderthal – Pierangelo Pirak (2016)

    The Last Neanderthal – Pierangelo Pirak (2016)

    Neandertals form a curious part of Human heritage. Fossil and genetic evidence suggest that the two Human populations split sometime between 400,000 to 800,000 years ago. Neandertals went extinct 30,000 years ago. For decades, the general impression about the Neandertals were as brutish, primitive beings. However the more we investigate the more we learn and become intrigued about these master ice age survivors. The director Pierangelo Pirak’s documentary is a concatenation of multiple short episodes exploring issues such as what […]

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  • Evolution Game – North Star Games (2014)

    Evolution Game – North Star Games (2014)

    The concept of evolution is one of the central themes in Nature Documentaries. A review of games designed to teach evolution in Nature Magazine prompted a search for other endeavors. Among the three games reviewed Evolution was evaluated as by far the best. There has been quite a few attempts to introduce evolution in game format. One game called “Life as a Lizard” is adapted as a role play in classroom setting. Another game also explores major tenets of evolutionary […]

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  • Pygmy Seahorses as Masters of Camouflage – Deep Look – PBS/KQED (2015)

    Pygmy Seahorses as Masters of Camouflage – Deep Look – PBS/KQED (2015)

    Environmental cues can have profound effects on the developmental trajectory of juveniles. When predatory dragonfly nymphs are present, tadpoles develop bigger tails with fast twitch muscles. Similarly the crustacean water fleas (Daphnia) develop helmet structures preventing fish to swallow them easily. Epigenetics is a relatively new branch of genetics but we have learned quite a lot in a few decades. The molecular mechanism of what evolutionary biologists described as phenotypic plasticity – biological ability to generate multiple phenotypes from a […]

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  • Sinister Cannibals or Nurturing Fathers?

    Sinister Cannibals or Nurturing Fathers?

    In majority of sexually reproducing species females are the choosy ones. Generally, females invest more in offspring during pregnancy and post-natal care. Males try many tricks (fighting with other males, making elaborate dances, providing nuptial gifts, carrying showy and difficult to maintain body ornaments etc.) to prevent being filtered out in female preferences. Parental investment is a determinant in choosiness. In this post we will take a look at a spectrum of male behavior in parental care. Pipefishes and mudskippers […]

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  • What Gall! The Crazy Cribs of Parasitic Wasps – Deep Look – PBS/KQED (2015)

    What Gall! The Crazy Cribs of Parasitic Wasps – Deep Look – PBS/KQED (2015)

    Another fascinating episode from a series produced by PBS/KQED: Deep Look… Gall formations are indeed one of the most interesting examples of plant-animal interactions. Gall-inducing wasps are plant parasites. The larvae hijack the chemical signaling pathways by secreting two plant hormones auxin and cytokinin which induce abnormal cell divisions leading to gall formation. In certain instances anthocyanin production pathways become upregulated and this gives most of the gall tissues their characteristic red color. Larvae also induce sugary secretions and literally […]

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  • Seed Dispersal by Dung Mimicry – Nature (2015)

    Seed Dispersal by Dung Mimicry – Nature (2015)

    Plant-animal interactions have not always evolved to become mutualistic win-win strategies like birds dispersing seeds of palms while feeding on the fruits. Plants can be rather deceptive. They can hijact sensory vulnerabilities of animals. Secondary metabolites such as nicotine, caffeine, codeine can be rather addictive. Plant chemicals can also be used as deterrent. A sub-Saharan desert plant taily weed (Ochradenus baccatus) detonates a mustard bomb in the mouths of seed predators who dare to chew and destroy its seeds. Plant […]

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  • First Footage of Deep-sea Angler Fish Mating – Kirsten & Joachim Jakobsen / Science (2018)

    First Footage of Deep-sea Angler Fish Mating – Kirsten & Joachim Jakobsen / Science (2018)

    A video recording of a female anglerfish attached to her mate created a wave of excitement among marine biologists. Anglerfish have a quite striking look for most people. This deep-sea adapted fish is well known by the public with their scary huge teeth and a light emitting lure. There are about 160 species of anglerfish worldwide. Most of what we know about these fishes have almost invariably came from dead specimens. Nobody has ever observed these animals in their natural […]

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  • Hungry Polar Bear Ambushes Seal | The Hunt | BBC Earth (2017)

    Hungry Polar Bear Ambushes Seal | The Hunt | BBC Earth (2017)

    Being a predator is very difficult. The “one in twenty” success rate is almost a universal rule of thumb to describe predator hunting efficiency. Prey defines the terms of engagement. Predator has to play catch up and therefore has to be stronger, faster more agile and perhaps more clever in planning a successful attack. We know this relationship from studies that have exquisitely measured predator-prey related physical parameters in Cheetahs and Lions hunting Impalas and Zebras. Connections between apex predators […]

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