A note on the fibre-optic light-guides in the eye photophores of watasenia scintillans

A brief account is given of the anatomy and fibre-optic-like light-guiding properties of rod-like elements in the eye photophores on the ventral surface of the eyeball of the Japanese firefly squid Watasenia scintillans.These light-guiding elements form a dominant proportion of the volume of the photophore (which is assumed to function in counter-illumination) and are aligned such that light from the bioluminescent core is directed in acone downwards from the eye. A coplanar arrangement of lamellae in the light-guides strongly suggests that the light passing through will be narrowly restricted both in wavelength and polarization. These features are discussedwith regard to other recent findings in this species

Cephalopods in neuroscience: regulations, research and the 3Rs

Cephalopods have been utilised in neurosci- ence research for more than 100 years particularly because of their phenotypic plasticity, complex and centralised nervous system, tractability for studies of learning and cellular mechanisms of memory (e.g. long-term potentia- tion) and anatomical features facilitating physiological studies (e.g. squid giant axon and synapse). On 1 January 2013, research using any of the about 700 extant species of ‘‘live cephalopods’’ became regulated within the European Union by Directive 2010/63/EU on the ‘‘Protection of Animals used for Scientific Purposes’’, giving cephalopods the same EU legal protection as previously afforded only to vertebrates. The Directive has a number of implications, particularly for neuroscience research. These include: (1) projects will need justification, authorisation from local competent authorities, and be subject to review including a harm-benefit assessment and adherence to the 3Rs princi- ples (Replacement, Refinement and Reduction). (2) To support project evaluation and compliance with the new EU law, guidelines specific to cephalopods will need to be developed, covering capture, transport, handling, housing, care, maintenance, health monitoring, humane anaesthesia, analgesia and euthanasia. (3) Objective criteria need to be developed to identify signs of pain, suffering, distress and lasting harm particularly in the context of their induction by an experimental procedure. Despite diversity of views existing on some of these topics, this paper reviews the above topics and describes the approaches being taken by the cephalopod research community (represented by the authorship) to produce ‘‘guidelines’’ and the potential contribution of neuroscience research to cephalopod welfare

The contribution of molecular data to our understanding of cephalopod evolution and systematics: a review

Figure 2. Polyploidy scenario suggested by and reproduced from Bonnaud et al. (2004). Updated diploid chromosome numbers (see Table 2) for the various branches are now Nautiloidea 52; Octopoda 56–60; Sepiolida 74; Sepiida 48–112; Myopsida 86–92 (?22-?172).Published as part of Allcock, A. Louise, Lindgren, A. & Strugnell, J.M., 2014, The contribution of molecular data to our understanding of cephalopod evolution and systematics: a review, pp. 1373-1421 in Journal of Natural History 49 (21) on page 1392, DOI: 10.1080/00222933.2013.825342, http://zenodo.org/record/400623