| dc.contributor.author | Hoar, Jennifer Anne. | en_US |
| dc.date.accessioned | 2014-10-21T12:37:08Z | |
| dc.date.available | 1995 | |
| dc.date.issued | 1995 | en_US |
| dc.identifier.other | AAINN08759 | en_US |
| dc.identifier.uri | http://hdl.handle.net/10222/55084 | |
| dc.description | From the deep sea giants to the smallest planktonic larvae, virtually all squid need and use fins for swimming, despite being archetypal jet-propelled animals. Fins vary, not only in final adult shape (i.e. small, triangular; long, marginal; or large, rhomboid) and throughout ontogenetic growth, but also with the lifestyle of the squid species. The morphometric changes occurring to both body and fins in 126 loliginid squid (Loligo forbesi, L. pealei, L. vulgaris reynaudii, L. opalescens, Lolliguncula brevis and Sepioteuthis lessoniana) were studied over a billion-fold size range in this thesis. These species all belong to the Family Loliginidae and are shallow-water, coastal species with similar lifestyles. The shape of the fins in these species is very similar and an optimal width to length ratio was indicated for these long-finned adults. Also, the final fin length appears to be determined, not by species, but by the size the squid attains during growth. | en_US |
| dc.description | The changes in fin shape with growth and species can also be related to hydrodynamic forces such as drag and thrust and to how these forces change with scale from viscosity-dominated at hatching to inertia-dominated as adults. In consideration of these forces, not only does the squid's body undergo a marked shape change with growth, from relatively globular to slender and streamlined, but the aforementioned fin shape change also assists in this goal. From the morphometric analysis, a model for swimming was developed that can be used over the large size range and can be manipulated to reflect the changes that the squid can produce during jetting (i.e. funnel diameter changes, jet frequency changes and/or changes in mantle volume utilized). The effect of fins on drag was included in this model and the effect of fin size on swimming forces studied. Fin use in three differently sized squid, L. forbesi, L. brevis, and S. lessoniana, was studied to gain insight into the jet assisted finning (JAF) used by these long-finned squid. Efforts to quantify the swimming efficiency of these animals demonstrated the need for appropriate new approaches to animals using two distinct, but synergistic modes of propulsion. | en_US |
| dc.description | Thesis (Ph.D.)--Dalhousie University (Canada), 1995. | en_US |
| dc.language | eng | en_US |
| dc.publisher | Dalhousie University | en_US |
| dc.publisher | | en_US |
| dc.subject | Biology, Anatomy. | en_US |
| dc.subject | Biology, Zoology. | en_US |
| dc.subject | Biophysics, General. | en_US |
| dc.title | The changing role of fins in growing loliginid squid (Mollusca; Cephalopoda). | en_US |
| dc.type | text | en_US |
| dc.contributor.degree | Ph.D. | en_US |
