Publication Date:
2017-07-05
Description:
Capture and manipulation of prey is the primary function of the arnis in cephalopods, but they also take on various other prehensile functions as well as propulsive ones (e.g. 'walking’ in octopus). In many instances they act as visual signal effectors as well. The entire arm crown can be involved in concerted actions, or individual pairs of arnis (or an individual arm in the case of certain hectocotyli) can act in a discrcte manner.
This paper discusses the problem of arm identity and homology in order to provide a basis for the comparison of arm action patterns and arm postures in different cephalopod groups. Emphasis is placed on data derived from the morphogenetic pathway that leads from a uniform embryonic anlage, through
subdivision into distinct arm rudiments, to the differentiation of arms. These data Support the homology between the arm crowns of decapods and octopods. Furthermore, there is good evidence for the homology of arm pairs at three positions: dorsal arms, ventral arms. ventrolateral arms (=tentacles of decapods).
Type:
Article
,
PeerReviewed
Format:
text
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