Hundert Jahre altes Rätsel der Evolution gelöst Vom Boden in die Höhe: Anders als bei vielen Reptilien stehen die Beine von Säugetieren unter dem Körper statt seitlich – erst dies macht Hund, Pferd und Co zu effizienten Läufern. Doch wie und wann dieser tiefgreifende Wandel der Körperhaltung stattfand, ist seit hundert Jahren eines der großen Rätsel der Paläontologie. Jetzt liefert eine neue Studie überraschende Antworten – und wirft gängige Vorstellungen zum Gang der Säugetiere über Bord.

Hundert Jahre altes Rätsel der Evolution gelöst https://wp.me/p36Ae-1cqk Anders als bei vielen Reptilien stehen die Beine von Säugetieren unter dem Körper statt seitlich – erst dies macht Hund, Pferd und Co zu effizienten Läufern. #Evolution #Säugetiere #Gang #parasagittal

Left: Phylogeny of tetrapods showing the evolution of posture from sprawling (green, yellow) to upright or parasagittal (orange), illustrated with humeri of select living and fossil species to show changes in morphology over time. Image credit Robert Brocklehurst. Right: The adaptive landscape of posture evolution in mammals and their ancestors. Living and fossil species with sprawling vs upright postures occupy different adaptive peaks. Image credit Magdalen Mercado.

How did our mammalian #posture arise from our sprawling #synapsid ancestors? @docrobbrock.bsky.social &co reveal #parasagittal postures in stem therians, implying that synapsids evolved & radiated with distinct forelimb trait combinations for most of their history @plosbiology.org 🧪 plos.io/4loAHoy

Left: Phylogeny of tetrapods showing the evolution of posture from sprawling (green, yellow) to upright or parasagittal (orange), illustrated with humeri of select living and fossil species to show changes in morphology over time. Image credit Robert Brocklehurst. Right: The adaptive landscape of posture evolution in mammals and their ancestors. Living and fossil species with sprawling vs upright postures occupy different adaptive peaks. Image credit Magdalen Mercado.

How did our mammalian #posture arise from our sprawling #synapsid ancestors? @docrobbrock.bsky.social &co reveal #parasagittal postures in stem therians, implying that synapsids evolved & radiated with distinct forelimb trait combinations for most of their history @plosbiology.org 🧪 plos.io/4loAHoy

Left: Phylogeny of tetrapods showing the evolution of posture from sprawling (green, yellow) to upright or parasagittal (orange), illustrated with humeri of select living and fossil species to show changes in morphology over time. Image credit Robert Brocklehurst. Right: The adaptive landscape of posture evolution in mammals and their ancestors. Living and fossil species with sprawling vs upright postures occupy different adaptive peaks. Image credit Magdalen Mercado.

How did our mammalian #posture arise from our sprawling #synapsid ancestors? @docrobbrock.bsky.social &co reveal #parasagittal postures in stem therians, implying that synapsids evolved & radiated with distinct forelimb trait combinations for most of their history @plosbiology.org 🧪 plos.io/4loAHoy