 According to the somatic twist hypothesis, not the entire animal turned on its back but just the ″somatic″ part , i.e., everything behind the eyes, mouth and nostrils, including the forebrain.
<fluency>  According to the somatic twist hypothesis, not the entire animal turned on its back but just the ″somatic″ part , i.e., everything behind the eyes, mouth and nostrils, including the forebrain.
 According to the somatic twist hypothesis, not the entire animal turned on its back but just the ″somatic″ part — i.e., everything behind the eyes, mouth and nostrils, including the forebrain.