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Barre d'outils Phylogène. Arbres phylogénétiques doc. 1. Arbres phylogénétiques doc. 2. Arbres phylogénétiques doc. 3. Mammifères 2 : les principaux groupes – Campbell 4e édition. Mammifères 1 : arbre phylogénétique simplifié – Campbell 4e édition. Arbre phylogénétique mammifères 10.1038:nature05634. Baleine : phylogénie et classifications. Acheter / Emprunter Pour réaliser un panier d’achat ou de prêt il est impératif d’être inscrit (onglet « inscrivez-vous »).

Baleine : phylogénie et classifications

Acheter Les films édités en DVD ou en vidéo VHS Pal sont vendus pour un usage privé ou institutionnel. Usage privé : droit de représentation dans le cercle de famille uniquement.Usage institutionnel : droit de visionnements individuels ou en groupe dans les locaux de l’organisme acquéreur (établissements d’enseignement, bibliothèques, associations, entreprises …). - Les projections avec programmation et publicité extérieure, même sans participation aux frais, directe ou indirecte, sont soumises à des conditions particulières : nous contacter.- La présentation de films pour des expositions, festivals, projections payantes… est soumise à des conditions particulières : nous contacter. Emprunter Prêts réservés aux institutions et professionnels de l’image pour visionnements individuels ou en groupe restreint. Pour toutes projections non commerciales : nous contacter. Les cétacés et leurs plus proches parents : 4 hypothèses phylogénétiques. Arbre phylogénétique des cétacés, données moléculaires & fossiles – Meredith et al. [2010]

Évolution des espèces : Les pattes des baleines. What is the Evidence for Evolution? - Stated Clearly [in English with subtitles] Transcript What is the evidence for evolution?

What is the Evidence for Evolution? - Stated Clearly [in English with subtitles]

The theory of Biological Evolution makes two very bold claims about living creatures: First: All living things on earth are related. They evolved from a common ancestor. Second: The evolution of living things is powered by natural processes. But is there really any evidence that these two claims are true? Yes. To keep things simple, here we’ll focus on Evolution’s first claim that: All living things on earth are related.

We cannot tackle the entire tree of life at once (after all there’s an estimated 8.7 Million species alive today), so instead we’ll focus most of our attention on one fairly small but fascinating branch of the evolutionary tree: Cetaceans. Biologist claim that all these creatures are closely related, and that the entire group evolved from an ancient 4 legged land mammal. Instead of taking their word for it, let’s look at the facts. Whales live in water and from a distance, they sort of look like giant fish. Meet Maiacetus. Fossil Spotlight: Meet Maiacetus, the Mother Whale! - Stated Clearly [in English]

Fossils of Maiacetus have been found in extremely good condition.

Fossil Spotlight: Meet Maiacetus, the Mother Whale! - Stated Clearly [in English]

The animals are about 8 1/2 feet long, lived a little over 47 million years ago, and are interpreted as amphibious whales that rested on land but lived and hunted at sea. What bones were found? The species is known from three individuals, all of which were found in the Habib Rahi Rock Formation of Pakistan: One male skeleton, fully intact, with only minor erosion on the snout and tips of backbone ridges.

See illustration above. What Good is Half a Blowhole? - Stated Clearly [in English] The blowhole of a whale lets the creature breathe by simply breaking the water’s surface with the top of its head.

What Good is Half a Blowhole? - Stated Clearly [in English]

This allows the animal to take in air without slowing down during long migrations or fast pursuits, and to keep its eyes focused on points of interest underwater when searching for food or avoiding predators. As demonstrated in our animation What is the evidence for Evolution, embryology and comparative anatomy show us that the blowhole is actually a pair of modified mammal nostrils. They have migrated to the top of the head, and in some cases, fused together as one. The fossil record shows this migration happening slowly over millions of years. If you’re anything like me, you’re probably wondering what started that migration. The modern whale’s blowhole clearly gives it a survival advantage. Since we can’t go back to watch the process in real time, we must turn to the fossil record for clues. Origine et évolution des baleines et des dauphins [ATTENTION, cours de 2 h 30 !]

Charte stratigraphique internationale 2012.