Biologia
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Viaggio con Darwin
L'idea della serie In viaggio con Darwin/Il secondo giro attorno al mondo è semplice ed efficace: Darwin viene prelevato dalla sua attuale dimora a Westminster e ripete con Luca Novelli e i suoi compagni lo straordinario viaggio compiuto cento e settanta anni prima. Per l'occasione è tornato giovanotto, ovvero ventiduenne, come quando fu invitato per la prima volta a bordo del Beagle dal Capitano FitzRoy. Darwin rivede i luoghi del suo primo viaggio a bordo del Beagle e fa inevitabili confronti.
This article explores the hypothesis that key human adaptations evolved in response to environmental instability. This idea was developed during research conducted by the Smithsonian’s Human Origins Program. Natural selection was not always a matter of ‘survival of the fittest’ but also survival of those most adaptable to changing surroundings.
Climate Effects on Human Evolution
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We are excited to announce the release of the EarthViewer app for iPad®. Click here for download instructions, screenshots, and related resources. What caused dinosaurs to disappear from the planet? How do species evolve?
The Tree of Life Web Project (ToL) is a collaborative effort of biologists and nature enthusiasts from around the world . On more than 10,000 World Wide Web pages, the project provides information about biodiversity, the characteristics of different groups of organisms, and their evolutionary history ( phylogeny ). Each page contains information about a particular group, e.g., salamanders , segmented worms , phlox flowers , tyrannosaurs , euglenids , Heliconius butterflies , club fungi , or the vampire squid . ToL pages are linked one to another hierarchically, in the form of the evolutionary tree of life.
Tree of Life Web Project
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A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's accreditation program is the first of its kind, requiring compliance with 53 standards of quality and accountability, verified by independent audit. A.D.A.M. is among the first to achieve this important distinction for online health information and services.Animaux, éthologie, écosystêmes
The Tree of Life Web Project (ToL) is a collaborative effort of biologists and nature enthusiasts from around the world . On more than 10,000 World Wide Web pages, the project provides information about biodiversity, the characteristics of different groups of organisms, and their evolutionary history ( phylogeny ). Each page contains information about a particular group, e.g., salamanders , segmented worms , phlox flowers , tyrannosaurs , euglenids , Heliconius butterflies , club fungi , or the vampire squid .
Tree of Life Web Project
Sono sicura che se questo articolo fosse stato pubblicato da una qualsiasi rivista, che non fosse Pikaia, nessuno si sarebbe soffermato su questo titolo. Ma in questo contesto il termine Burgess Shale ha un significato unico, qualcosa che tutti conoscono ed ha un valore evolutivo immenso! Ma vediamo di fare chiarezza per “i non addetti ai lavori”.
Anomalocaris strikes back!
Fireflies (Coleoptera: Lampyridae) « Teaching Biology
The Lampyridae Raffinesque 1815 are the beetles commonly known as fireflies and lightning bugs. There are over 2000 species in over 100 genera, with this being a quarter of the expected diversity (Viviani, 2001). They’re found all over the world and in all sorts of habitats, including aquatic ones (Fu et al. , 2005). Their classification has classically not followed a phylogenetic system – as McDermott (1964) wrote, their classification “should not be construed as indicating phylogenetic relationship”. Of course, I don’t agree with such a view, being a paraphyly-hating systematist rather than a taxonomist. Lampyrid subfamilies are differentiated with easy-to-spot characters, such as the position of the light organs or the dorsal visibility of the head (how far under the pronotum it goes – it can be completely covered, as in cockroaches, or more exposed).