page_title: Leptictidium
section_title: Evolutionary tendencies
hierarchical_section_title: Leptictidium / Evolutionary tendencies
caption_attribution_description: Français&#160;: Lepticidium auderiense
context_page_description: Leptictidium is an extinct genus of small mammals that were likely bipedal. Comprising eight species, they resembled today's elephant shrews. They are especially interesting for their combination of characteristics typical of primitive eutherians with highly specialized adaptations, such as powerful hind legs and a long tail which aided in locomotion. They were omnivorous, their diet a combination of insects, lizards and small mammals. One of the first branches to split from basal eutherians, they appeared in the Lower Eocene, a time of warm temperatures and high humidity, roughly fifty million years ago. Although they were widespread throughout Europe, they became extinct around thirty-five million years ago with no descendants, probably because they were adapted to live in forest ecosystems and were unable to adapt to the open plains of the Oligocene.
context_section_description: In his work Quelques insectivores primitifs nouveaux de l'Eocène supérieur du sud de la France (1989), French paleontologist Christian Mathis studied the evolutionary tendencies of the genus Leptictidium, based on comparison of the most primitive and the most recent species. From his observations, Mathis remarks:
  an increase in size;
  a precocious merging of the hypoconulid and the entoconid on M3;
  a slight reduction of the width of the talonid on M3 in comparison to the anterior molars;
  the formation and development of a mesostile on the molariform jugal teeth P4-M3;
  the reduction of the parametastylar and metastylar regions of these same teeth (with some exceptions), in particular with a reduction of the parastylar lobe which rises less in the anterior part of M3 and possibly P4;
  a transverse shortening of the upper molarised teeth, which become more square;
  the development of accessory conuli on the preprotocrista and postprotocrista;
  the development of the postcingulum.
caption: Restoration
exif: {"Image Orientation": "Horizontal (normal)"}