... striated muscles and instead that length–force relationships vary with operating length range. To test these predictions, we measured length–force relationships of five obliquely striated muscles from inshore longfin squid, Doryteuthis pealeii : tentacle, funnel retractor and head retractor longitudinal...

... in a cephalopod, the two-toned pygmy squid ( Idiosepius pygmaeus ). We exposed squid to ambient (∼450 µatm) or elevated (∼1000 µatm) CO 2 for 7 days. Squid were treated with sham, the GABA A receptor antagonist gabazine or the non-specific GABA A receptor antagonist picrotoxin, before measurement of conspecific...

.... Squid Jellyfish Salps Swimming efficiency Pulsed jets Particle image velocimetry Animal locomotion and the impact of the fluid environment on the evolution of body forms in swimming animals has long been a focus of evolutionary and functional biologists (e.g. Thompson, 1961 ; Vogel, 2013...

... and neural responses to tissue injury in the sepiolid Euprymna scolopes (Hawaiian bobtail squid), which inhabits shallow tropical waters close to dense human habitation. Behavioral hypersensitivity and neural plasticity that occur normally after tissue injury were impaired both under chronic estrogen...

...Andrew M. Smith; Scott M. LaValva; Matthew M. Loiacono; Joseph T. Thompson ABSTRACT We have discovered features of the nuchal joint in the squid, Doryteuthis pealeii , that are unique compared with moveable joints in other animals. The joint's function is unclear but it allows the head to glide...

...Diana H. Li; William F. Gilly ABSTRACT Squids display a wide range of swimming behaviors, including powerful escape jets mediated by the giant axon system. For California market squid ( Doryteuthis opalescens ), maintaining essential behaviors like the escape response during environmental...

...Hannah E. Rosen; William F. Gilly ABSTRACT Seemingly chaotic waves of spontaneous chromatophore activity occur in the ommastrephid squid D osidicus gigas in the living state and immediately after surgical disruption of all known inputs from the central nervous system. Similar activity is apparent...

...Rachel A. Jastrebsky; Ian K. Bartol; Paul S. Krueger ABSTRACT Although squid are generally considered to be effective predators, little is currently known of how squid maneuver and position themselves during prey strikes. In this study, high-speed video and kinematic analyses were used to study...

...Carly A. York; Ian K. Bartol; Paul S. Krueger ABSTRACT Squid rely on multiple sensory systems for predator detection. In this study we examine the role of two sensory systems, the lateral line analogue and vision, in successful predator evasion throughout ontogeny. Squid Doryteuthis pealeii...

...Danna J. Staaf; William F. Gilly; Mark W. Denny Squid are the largest jet propellers in nature as adults, but as paralarvae they are some of the smallest, faced with the inherent inefficiency of jet propulsion at a low Reynolds number. In this study we describe the behavior and kinematics...

... of ocean acidification and warming. Here, we investigated a comprehensive set of biological responses to these climate change-related variables (2°C above winter and summer average spawning temperatures and ΔpH=0.5 units) during the early ontogeny of the squid Loligo vulgaris . Embryo survival rates ranged...

.... Invertebrates such as squid, however, may exhibit an alternative mechanism to tune contractile properties that is based on differences in muscle ultrastructure, including variable myofilament and sarcomere lengths. To determine definitively whether contractile properties of squid muscles are regulated via...

...William J. Stewart; Ian K. Bartol; Paul S. Krueger SUMMARY Although the pulsed jet is often considered the foundation of a squid's locomotive system, the lateral fins also probably play an important role in swimming, potentially providing thrust, lift and dynamic stability as needed. Fin morphology...

...Ian K. Bartol; Paul S. Krueger; William J. Stewart; Joseph T. Thompson SUMMARY The dynamics of pulsed jetting in squids throughout ontogeny is not well understood, especially with regard to the development of vortex rings, which are common features of mechanically generated jet pulses (also known...

...Ian K. Bartol; Paul S. Krueger; William J. Stewart; Joseph T. Thompson SUMMARY Squid paralarvae (hatchlings) rely predominantly on a pulsed jet for locomotion, distinguishing them from the majority of aquatic locomotors at low/intermediate Reynolds numbers ( Re ), which employ oscillatory...

...William M. Kier; Frederick H. Schachat SUMMARY Although muscle specialization has been studied extensively in vertebrates,less is known about the mechanisms that have evolved in invertebrate muscle that modulate muscle performance. Recent research on the musculature of squid suggests...

...Tsyr-Huei Chiou; Lydia M. Mäthger; Roger T. Hanlon; Thomas W. Cronin SUMMARY On every arm of cuttlefish and squid there is a stripe of high-reflectance iridophores that reflects highly polarized light. Since cephalopods possess polarization vision, it has been hypothesized that these polarized...

...Erik J. Anderson; Mark A. Grosenbaugh SUMMARY Although various hydrodynamic models have been used in past analyses of squid jet propulsion, no previous investigations have definitively determined the fluid structure of the jets of steadily swimming squid. In addition, few accurate measurements...

... diameter in low levels of illumination. * Author for correspondence (e-mail: r.h.douglas@city.ac.uk ) 15 11 2004 © The Company of Biologists Limited 2005 2005 pupil eye cephalopod squid octopus Eledone cirrhosa cuttlefish Sepia officinalis Invertebrates display...

... made over a 13 h period of video sequences. Allometry measurements were made on 157 squids ranging in size from 12 to 151 mm mantle length ( ML ). In addition to ML we measured the morphometric characters of fin length( FL ), fin width ( FW ), mantle width ( MW ), eye diameter ( ED ), head width ( HW...