Author: |
Top |
---|
Theodore Holmes Bullock
Department of Neurosciences and Neurobiology Unit
Scripps Institution of Oceanography
University of California, San Diego
9500 Gilman Drive DEPT 201
La Jolla, CA 92093-0201
Phone: (619) 534-3636
Fax: (619) 534-3919
e-mail: tbullock@ucsd.edu
Introduction |
Top |
---|
Whereas the neural analysis of behavior of planktonic species and stages has been relatively neglected, we have many clues that it is going to be rich, diverse and interesting. The aims of this contribution are to defend that statement, with selected examples, and to suggest that neural analysis, particularly sensory physiology, has great explanatory power of ecologically significant behavior.
I have to begin with a personal note about plankton, recalling the lasting impression made long ago by a film on invertebrates in the Arctic where scyphomedusan jellyfish were pulsing at a rate well within the range familiar in summer temperate waters, warmer by 20º C. I must have been influenced by this observation and my own experiences in a study of the neural basis of fluctuations in the rate of pulsation of medusae (Bullock 1943), some of which was made in December 1941 in Pensacola, where my wife and I collected Rhopilema cruising at random in the Sound, stopped now and then by Army bridge guards concerned about saboteurs in that first fortnight after Pearl Harbor. At any rate, by the early fifties about half of my laboratory group was devoted to the physiological ecology of temperature acclimation in marine invertebrates. That field, which I left in the early sixties, still offers a challenge in the ecologically fundamental question of why some species are able to acclimate much more than others. The proposal I made in 1955, that different rates in the same organism acclimate to different degrees, resulting in greater disharmony in some species than others, may still be viable and most likely applies to rate processes in sensory and central nervous functions, among others.
Medusae are large animals, relatively, although generally treated as planktonic. The first reaction from most workers when neurophysiology of plankton is mentioned concerns their small size or gelatinous nature. The first message I bring is not new but also not widely appreciated.
Small size and slipperiness are no excuse |
Top |
---|
Technics have been successfully developed to record nerve impulses from single neurons in zebra fish larvae (Eaton and Kimmel 1980). (Only one or a few sample citations are given, here and in the following, often representing a substantial literature). Many papers deal with electrical recording from small flies (Ogmen and Garnier 1994), even Drosophila (Wyman et al. 1984; Elkins and Ganetsky 1990; Engel and Wu 1992; Trimarchi and Schneiderman 1993) and mosquitoes, and from copepods (Yen et al. 1992). Single unit action potentials have been recorded from scyphomedusans (Horridge 1953), Clione (Arshavsky et al. 1988, 1991, 1992; Huang and Satterlie 1990; Satterlie 1993; Norekian 1989, 1993; Norekian and Satterlie 1993b), Melibe (Trimarchi and Watson 1992), a number of other opisthobranchs, and cephalopods (Maturana and Sperling 1963; Laverack 1980; Boyle et al. 1983; Bullock and Budelmann 1991) and larval fish (Eaton and Nissanov 1985 mentions a predatory protozoan causing escape responses in larval zebrafish; Eaton and DiDomenico 1986). Many studies have been done upon unanesthetized animals, free to move and behave, within limits.
Behavior turns up new senses and forms of recognition to be accounted for |
Top |
---|
The chief source of clues to sensory biology and interesting neuroethology of zooplankters is the close observation of their behavior and responses. I will cite some examples that present opportunities for new analysis of their neural bases.
Responses to pure hydrostatic pressure stimuli have been reported in a number of species (Morgan 1984; Forward, this volume). Following earlier suggestions from much greater stimulus intensities, Knight-Jones and Qasim (1955) Baylor and Smith (1957) and Enright (1961, 1962, 1963, 1967) found responses to changes in pressure as low as 10 cm of water or 10 millibars (mb). Knight-Jones and Qasim provided no details about their experimental methods but reported up-swimming to increases and down-swimming to decreases of 10 mb in Carcinides and Galathea megalops larvae. Baylor and Smith found lower thresholds in pteropods and copepods (Pontella, Temora) and, like the previous authors, thresholds of < 1 atmosphere in annelids, hydromedusae, chaetognaths, ctenophores, copepods and others. According to my memory of their verbal presentation, though not in the brief printed version, Baylor and Smith, in one type of experiment, watched individual zooplankters in a vertical glass cylinder, swimming up and down within a range of a few centimeters. They then raised or lowered a leveling bulb connected to the cylinder - whose top was closed - by a flexible U-tube, following each vertical movement of the animal. Keeping the pressure constant at the level of the animal, it increased its vertical excursion markedly, as though lacking the normal change-of-pressure feedback. This behavior implies a non-drifting, absolute pressure sense. Baylor and Smith report that a 15 cm stimulus causes a 15 cm response in the compensatory direction. They emphasized that reliable responses require animals brought in with extreme care to avoid pressure or pH or other shocks. Depth compensating responses by planktonic animals had been reported in some species to persist with undiminished intensity for several hours (Hardy and Bainbridge 1951, who used stimuli in the 500 mb range), and have therefore been interpreted as indicating a sort of "barostat" by which the animals might maintain constant depth, to within a few meters in the sea.
In contrast to the sustained type of response, which requires a tonic receptor, Enright observed transient but intense behavioral responses in Synchelidium sp., an intertidal, predominantly benthic amphipod. He did not exclude their having some sustained sense but showed the importance of the phasic component. He started with many amphipods in a closed jar of sea water, most of them resting on the bottom. Raising the leveling bulb or adding small weights to a piston, both of which were done in the next room, in double blind experiments, caused many animals to swim about vigorously for a few seconds. Decreasing the pressure caused transient reduction of ongoing spontaneous activity. He later found similar responses in the anomuran Emerita, particularly the megalops larval stages, immediately after they have settled following a prolonged planktonic development. He excluded the possibility of small gas bubbles, and we have no precedent for other structures with appreciable compressibility different from aqueous tissues or with piezoelectric properties immersed in aqueous tissues. Digby (1961) proposed a mechanism involving a monolayer of gas but his evidence has not been generally accepted. Even in the best studied species, Emerita, we do not know where the reception occurs. Enright has observed responses in some individuals after removal of all periopods or all four antennae or both eyes (pers. comm.). I believe a hitherto unknown sense organ, indeed a new class of sense organs is awaiting discovery. Only after localizing and identifying the organ can we expect to deduce the detection principle it employs.
Mechanoreceptors for water movement and vibration are probably among the most amenable to new physiological study (Newbury 1972 in chaetognaths; Wiese and Marschall 1990 in euphausids). Lateral line-like sense organs have been reported in penaeid shrimps (Denton and Gray 1985) and in cuttlefish (Budelmann this volume; Budelmann and Bleckmann 1988; Budelman 1989; Budelmann et al. 1991; Bleckmann et al. 1991a; Bleckmann 1994).
Also awaiting discovery in zooplankton are temperature receptors, especially those with a non-adapting, thermometer-like response that can explain the known behavioral response manifested by a consistent thermopreferendum. It has been repeatedly pointed out that at least teleosts and probably many taxa and stages of development show an ability to stay in a layer of water of a preferred temperature, to within a fraction of a degree, i.e. close to an isotherm. It seems unlikely that this is explainable in the general case by a parallel isodensity (Forward 1989b and this volume) or other clue. If it is, then yet another non-adapting sensory receptor is to be sought. Thermometer organs are well known in mammals, including those that are excited by increases in temperature in the normal living range ("warm receptors") and those that are excited by decreases in temperature in this range ("cold receptors"). They are believed to occur in fish and other exothermic taxa but a convincing demonstration of specific temperature sense organs is an outstanding opportunity (Späth 1978), particularly in zooplanters. The adapting aspect of sense organ response, i.e. a temperature rate-of-change sensibility is likely to be found first, either in separate receptors or as an initial part of the response of thermometer-like receptors (Forward 1990b and this volume). But, the experience with the ampullae of Lorenzini of elasmobranchs warns us to be cautious; they were first thought to be very sensitive temperature change receptors (Sand 1938) and only later this modality was shown not to be the normal adequate stimulus (Bullock 1974).
Chemoreceptors are indicated by many behavioral observations which, moreover, point to high specificity and sensitivity Lazzaretto et al. 1990; Demott and Watson 1991; Kassimon and Hufnagel 1992; Snell and Morris 1993; Bollens et al. 1994, to cite only some of the more recent reports).
Some kinds of behavior have yet to be found, but I believe, will be found in zooplankters and will then trigger the search for the organs mediating it. An example is magnetic orientation, known in bacteria (Kalmijn 1978; Blakemore et al. 1980), where the behavior is apparently adequately accounted for by a known organelle. The behavior has often been claimed for birds and insects but no sense organ or identified transducer has been convincingly shown as yet. Lohmann et al. (1991) report a particular pair of cells in the gastropod, Tritonia, that alter their firing in response to changes in earth-strength magnetic fields; the same field changes do not influence any of 50 other cells.
Magnetic orientation as an indirect consequence of highly sensitive electrosensory organs and central pathways and processors able to extract this information and use it in normal behavior, has been shown in elasmobranchs (Kalmijn 1988). A similar sense exists in some quite small teleosts, marine (Plotosus, Arius, Siluriformes), as well as freshwater (Siluriformes, Gymnotiformes, Mormyriformes and one subfamily of Osteoglossiformes). At present, however, none but the elasmobranchs are known to have an adequately high sensitivity to make use of the currents induced by motion in the earth's magnetic field. Still, neither the sensitivity in these groups, already known to be electrosensitive, nor the existence of this sense in other taxa, both vertebrate and invertebrate, can be categorically ruled out. I anticipate new findings of both electrosense and direct magnetic sense.
Other forms of behavior are quite familiar and yet the sensory modalities involved are only partly or little known. Schooling in teleosts and other groups, including members of the zooplankton, seems likely to depend on more than one sense in different species and conditions (Partridge and Pitcher 1980). I doubt that our present understanding, based on a few species, is a representative picture of this widespread class of behaviors. To mention one example, Kalmijn (personal communication) has suggested that the dense schools of the marine catfish, Plotosus, may under some conditions use their electrosense to keep together.
Other familiar behaviors whose sensory bases are rarely or little known are predator avoidance, prey detection, conspecific communication and mate recognition. Data on fish kairomones that influence the avoidance or swarming behavior of Daphnia are presented elsewhere in this volume (Larsson; Ringelberg and van Gool; DeMeester). Finicky settlement of barnacle, polychaete and other larvae upon substrates according to its "taste" or texture is well known (Johnson and Strathmann 1989; Harvey 1993; Dineen and Hines 1994; Forward, Zimmer-Faust this volume). Long ago I reviewed the literature on predator recognition by invertebrates and found few examples at that time, apart from scallops and freshwater snails (Planorbis); I reported observations of limpets and abalones fleeing from a starfish tubefoot (Bullock 1953b). Specific chemical signals must be much more common than we then appreciated. The swimming escape response triggered by a brief contact with starfish tubefeet in the sea anemone, Stomphia (Wilson 1959) and the nudibranch, Tritonia, (Willows and Hoyle 1969) have been studied physiologically; in the latter case a network of neurons was identified that makes the decision whether to trigger the prolonged behavior.
Complex visual form recognition is indicated by behavior such as the use of dozens of distinct color patterns for as many social signals, shown by Moynihan and Rodaniche (1982) in a Carribean squid (Sepioteuthis). Startle responses are a fertile field, convenient for sensory analysis because they are relatively stereotyped and hence successive experiments are likely to represent the same behavior. In the wide variety of taxa where they are found, different adequate stimuli are known, from a moving shadow to a tap or an acoustic click (Eaton 1984). Mackie (1990) has pointed out interesting parallels between the giant fiber jet swimming in squid and jellyfish, a form of behavior that is not sterotyped but quite flexible (Otis and Gilly 1990). Careful experimental ethology may reveal that in some cases several stimuli of different modalities may function in sequence to bring an animal into close proximity with a desirable target or prime it to be more sensitive to some forthcoming event.
A point of view makes you a neuroethologist |
Top |
---|
Ecologically significant behavior opens another dimension when we begin to uncover the mechanisms in sensory physiology, central analysis of sensory input, recognition of species characteristic sign stimuli, plastic modulation by age, state or other sensory inputs, selection of response from the species repertoire and neural control of effectors. With emphasis on the sensory side, I will illustrate with a selection of examples from near-planktonic or related or paradigmatic species that have received some successful study. These are intended to underline the opportunities and needs in further extension to the great range of planktonic taxa. It is important to note that, whereas some started with known behavior to be accounted for, others began as bottom-up or inside-to-outside or anatomy-to-physiology curiosity. Sometimes the relevant behavior has yet to be defined.
A good example is the discovery of a sensory system in cephalopods - actually in young, planktonic cuttlefish (Sepia), that appears to be an analogue of the lateral line system in aquatic vertebrates (Budelmann and Bleckmann 1988; Budelman 1989; Budelmann et al. 1991; Bleckmann et al. 1991a; Bleckmann 1994). Anatomical suggestions of possibly sensory structures are widespread (Hayashi and Yamane 1994; Jensen et al. 1994) and led the physiologists in this case to look for responses in the rows of cutaneous organs on the head. They proved to be responsive to disturbances in the water and not to other stimuli - a new modality for molluscs.
Quite a different story is represented by a recent finding in a classical sense organ in a squid (Alloteuthis), the statocyst. Here Williamson (1989) surprises us with the demonstration of electrical coupling between secondary hair (sense) cells - a step toward uncovering the cellular mechanisms of reception. Arkett and Mackie (1988) have shown the sensory hair cells for mechanoreception in the planktonic medusan, Aglantha, to be amenable to physiological study. The same must be true for water movement sensors in many other groups (Budelmann 1989; Bleckmann 1994). The sharp distinction found in vertebrates between the lateral line and the inner ear reception of disturbance in the aquatic medium outside the animal has yet to be properly compared with an adequate sampling of invertebrate systems. A large literature exists on the physiology and anatomy of hearing in fish (Atema et al. 1988; Kalmijn 1988; Popper, this volume), including some small enough to be marginally planktonic and including very young sharks (Bullock and Corwin 1979). A smaller but substantial literature exists on the lateral line (Coombs et al. 1989). One feature of the octavolateral sense organs of vertebrates which may have deep significance for their function in planktonic stages of fish is that the number of sensory hair cells increases with size dramatically. Presumably this confers greater ability to detect feeble signals and one has to wonder whether larvae and young fish are relatively deaf. Whereas well controlled behavioral experiments on adequately motivated animals are the final arbiter, simple electrophysiological endpoints may often be the first way to study such questions as the upper frequency limit of hearing or the influence upon hearing of the developing swim bladder and, in some species, its later disappearance. We found in young yellow-tail tuna (Thunnus albacares) that brain responses to inner ear reception cut off sharply above the remarkably low frequency of 350 Hz, even lower than an earlier report based on conditioned responses in two specimens (Iversen 1967; Bullock, Brill and McClune, unpublished experiments).
Electroreception has already been alluded to. Many species of agnathans, holocephalans, teleosts and others have been shown to be electroreceptive - more readily by physiological than by behavioral responses (Bullock et al. 1961; Bullock and Heiligenberg 1986; Fields et al. 1993). Other taxa with this sense modality seem likely to be found, especially among teleosts, but small size confers a serious disadvantage. Sometimes the technic for recording from single receptors is exceedingly simple and requires no surgery (Viancour 1979; DeWeile 1983).
Photoreception and vision have attracted much attention among invertebrates (Therman 1940; MacNichol and Love 1960a, b; Wiersma et al. 1961; Waterman and Wiersma 1963; Gwilliam 1963; Hartline and Lange 1974; Lange and Hartline 1974; Lange et al. 1974; York and Wiersma 1975; Schiff 1987, 1989; Cronin et al. 1994) including a few studies on planktonic forms (Smith and Macagno 1990; Frank and Widder, this volume). I expect many adaptive specializations to be found among zooplankters - for detecting color, moving shadows, dim light and the like. One which could be overlooked we found in the young tuna midbrain; optic lobe responses show a high flicker fusion frequency, approaching some of the fast eyes in certain insects and nearly double that in humans - presumably an adaptation to aid vision during rapid swimming (Bullock, Brill and McClune, unpublished).
What is taste and what is olfaction? Why are they so distinct in the peripheral and central structures that mediate them in the vertebrates - already in aquatic taxa, long before terrestrial forms evolved? These questions come primarily from the anatomy and physiology but depend on ethology and ecology for essential clues. Taxa differ greatly in the mechanisms of chemoreception and comparative physiology is essential, in parallel with comparative behavior, to understand the dynamic range, degree of specificity, temporal and spatial resolution of these senses.
I like to tell how important taste was in the history of the Scripps Institution of Oceanography and of the unique concentration of neuroscientists in La Jolla. Yngve Zotterman, Professor of Physiology at the Royal Veterinary College in Stockholm, was a prominent comparative physiologist of gustation. He started the series of international congresses on Olfaction and Taste, of which the volume edited by Kurihari, Suzuki and Ogawa (1994) is the eleventh. He visited his fellow Scandinavian, Per Scholander, in La Jolla, in 1959. Scholander was a comparative physiologist of respiration, cardiovascular, water and salt functions and got Zotterman to support his idea of a laboratory vessel dedicated to comparative physiology and biochemistry by showing how he would set up to record nerve impulses from taste fibers in teleosts on board one of the smaller Scripps vessels at sea. Yngve didn't succeed on that trip but supported Pete's idea, which led shortly to the R/V Alpha Helix. After that, one thing led to another until Pete and others at S.I.O. recruited the first neuroscientist to La Jolla, in 1965 - Susumu Hagiwara, who was followed by a swelling stream of like ilk, now many hundreds strong, more than a score of them doing marine biology. In spite of a substantial literature (represented in our reference list by Finger and Silver 1987, Atema 1994, Atema and Voigt 1995), the spectrum of taste receptors and even more of olfactory receptors is still only fragmentarily known, even in the most studied arthropods, molluscs and fish.
In order to do justice to the ecologically significant neuroethology of zooplankters, we have to look a bit farther along the central nervous pathways from sense organ to behavior. I will mention only a few examples from taxa that include planktonic members deserving study.
Giant fiber systems have been evolved again and again, convergently, among the phyla and classes; even orders and families may differ profoundly in the development of these systems (Bullock 1948a, 1953a), usually associated with startle responses and the first phase of escape (Eaton 1984). They are quite amenable to study in small forms, as already pointed out for Drosophila (Wyman et al. 1984), even with extracorporeal, non-invasive electrodes (Featherstone and Drewes 1991). The meaning of the giant fiber diameter cannot always be its greater velocity, for in small animals like Drosophila the absolute saving in time is small. Nevertheless, in some shrimp, adaptations of the giant fiber for high velocity result in phenomenally fast axons - by far the fastest known (Fan et al. 1961; Huang and Yeh 1963; Hsu et al. 1964, 1975a, b; Hao and Hsu 1965; Kusano 1965, 1966, 1971; Hsu 1982; Terakawa and Hsu 1991). This is an elegant case where a simple property revealing a remarkable specialization was overlooked for decades, even though shrimp giant fibers had been studied and shown to be unusual (Holmes et al. 1941).
Motor output, its patterning, and central and peripheral organization intimately complement the sensory input and are sure to be of interest in zooplankters. Some illustrative studies include that of Spencer (1988) showing non-spiking interneurons in the swimming system of a pteropod and of Arshavsky et al. (1988) who found nonsynaptic interaction - both discoveries being of general neurobiological import. Arshavsky et al. (1991, 1992) and Satterlie (1993) represent a series of studies of the organization of the swimming system in these gastropods. Wilson (1960) studied the nervous control of movement in annelids, and Bowerman and Larimer (1976) that in crustaceans. A number of chapters in Sandeman and Atwood (1982) and Wiese et al. (1990) have relevant recent examples. Moss and Tamm (1993) show that even the delicate movements of ctenophores can be successfully studied with electrophysiological methods. Important effectors other than moving major parts of the body include the chromatophores. Some studies on them and their control underline the opportunities (Cooper et al. 1990; Hanlon et al. 1990; Novicki et al. 1990), especially when cephalopods in good condition can be as readily available as they are now (Hanlon et al. 1978, 1983). Nervous control of luminescence is also interesting and approachable (Nicol 1960; Baxter and Pickens 1964; Latz et al. 1990; Bowlby and Case 1991; Bannister 1993).
Anatomy has many new tools and rich rewards |
Top |
---|
Although our symposium emphasizes sensory ecology and physiology, I must call attention to the opportunities for advancing both of them through anatomical investigation. The armamentarium of available new methods, especially those applicable to revealing neural organization has expanded dramatically in recent years and most of the newer procedures have yet to be exploited on zooplankters. Immunocytochemistry, intracellular dyes and markers transported throughout a neuron and its processes, even in fixed material, laser confocal microscopy and the use of optical signals of activity, with or without voltage-sensitive dyes are some of the technics now in use for identifying and tracing nerve cells and their connections, distinguishing among types of neurons and visualizing active neurons. A limited selection of examples concern the retina (Saidel 1980; Saidel et al. 1983; Cronin et al. 1994; Arikawa and Matsushita 1994; Becerra et al. 1994; Evans et al. 1993; Munz and McFarland 1977). A selection on other sensory and central structures is represented by the reports of Tamm and Tamm 1990; Bollner et al. 1991; Bundy and Paffenhofer 1993). Many sense organs have been long known anatomically, or more recently recognized, but are still without any secure assignment of function. An example is the dorsal organ of many crustaceans, including planktonic taxa (Laverack and Sinclair 1994).
The coda integrates the themes and leitmotifs |
Top |
---|
Our organizers have rightly called attention to the great gap in understanding the principal fauna of the bulk of the biosphere. However complete our list of species, our zoogeography, foodwebs, and life histories, we cannot claim understanding before we know a good deal concerning what each zooplankter does about food, enemies, mates and other conspecifics, diurnal and seasonal states, what it can recognize and discriminate, what behavior follows each adequate stimulus, the pattern of succession of the behavioral repertoire - and the sensory and neural apparatus that accomplishes vital tasks.
A major development in zoological neurology in the last quarter century has been the discovery that many taxa of invertebrates have a large proportion of their nerve cells unique and identifiable in every specimen, making it possible, bit by bit, to piece together all or nearly all of the circuitry. This should apply at least as much to the zooplankters as to the bulky lobsters and sea slugs. Such encouragement, combined with the message documented above, that small size and slipperiness need not prevent microelectrode recording with controlled stimulation, makes it clear that the time is ripe and the technics available to make real inroads into this massive agenda. The clues and precedents from work already accomplished by pioneers in the area also make it clear that we can expect surprises and major discoveries, not simply smaller versions of familiar neuroethology. Zooplankton, in its marvellous variety, faces a set of problems in everyday living different from those of benthic, littoral and other faunas and not at all uniform or uneventful as we might imagine from our human perspective on their watery world. I look forward to the next convening of this range of specialists since it seems certain that in the interim this meeting will have sparked an abundance of new efforts and fascinating stories.
References |
Top |
---|
The following list includes titles cited in the text and, at the request of the Editors, others relevant to the subject, selected mainly from recent literature. For the sake of length, many important older references are not included.
Arikawa K, Matsushita A (1994) Immunogold co-localization of opsin and actin in Drosophila photoreceptors that undergo active rhabdomere morphogenesis. Zool Sci 11:391-398
Arkett SA, Mackie GO (1988) Hair cell mechanoreception in the jellyfish Aglantha digitale. J Exp Biol 135:329-342
Arshavskii YI; Orlovskii GN; Panchin YV. (1991) Electrophysiological study of serotoninergic neuron C1 in the pteropod mollusk Clione. Neurophysiology 23:14-20
Arshavsky YI, Deliagina TG, Orlovsky GN, Panchin YV, et al. (1992) Interneurones mediating the escape reaction of the marine mollusc Clione limacina. J Exp Biol 164:307-314
Arshavsky YI, Deliagina TG, Gelfand IM, Orlovsky GN, Panchin YV, Pavlova GA, Popova LB (1988) Non-synaptic interaction between neurons in molluscs. Comp Biochem Physiol 91C:199-203
Atema J, Voigt R (1995) Sensory biology and behavior. In: The Biology of the Lobster, Homarus americanus. J Factor, ed. Academic Press, New York
Atema J (1994) Turbulent odor dispersal, receptor cell filters, and chemotactic behavior. In: Olfaction and Taste XI. K Kurihara, N Suzuki, H Ogawa, eds. Springer-Verlag, New York
Atema J, Fay RR, Popper AN, Tavolga WN (1988) Sensory Biology of Aquatic Animals. Springer-Verlag, New York, 923 pp
Atwood HL, Govind CK (1990) Activity-dependent and age-dependent recruitment and regulation of synapses in identified crustacean neurones. J Exp Biol 153:105-127
Atwood HL (1973) An attempt to account for the diversity of crustacean muscles. Am Zool 13:357-378
Bannister NJ (1993) Innervation of luminous glands in the calanoid copepod Euaugaptilus magnus. J Mar Biol Assoc UK 73:417-423
Baxter C, Pickens PE (1964) Control of luminescence in hemichordates and some properties of a nerve net system. J Exp Biol 41:1-14
Baylor ER, Smith FE (1957) Diurnal migration of plankton organisms. In: Recent Advances in Invertebrate Physiology. BT Scheer, TH Bullock, LH Kleinholz, AW Martin, eds. Univ Oregon Publications, Eugene, OR, pp 21-35
Becerra M, Manso MJ, Rodriguezmoldes MI, Anadon R (1994) The structure and development of dopaminergic interplexiform cells in the retina of the brown trout, Salmo trutta fario - a tyrosine hydroxylase immunocytochemical study. J Anat 185:377-385
Blakemore RR, Frankel RB, Kalmijn AJ (1980) South-seeking magnetotactic bacteria in the southern hemisphere. Nature 286:384-385
Bleckmann H (1994) Reception of hydrodynamic stimuli in aquatic and semiaquatic animals. Fortschr Zool 41:i-ix, 1-115
Bleckmann H, Budelmann BU, Bullock TH (1991a) Peripheral and central nervous responses evoked by small water movements in a cephalopod. J Comp Physiol A 168:247-257
Bleckmann H, Breithaupt T, Blickhan R, Tautz J (1991b) The time course and frequency content of hydrodynamic events caused by moving fish, frogs, and crustaceans. J Comp Physiol A 168:749-757
Bollens SM, Frost BW, Cordell JR (1994) Chemical, mechanical and visual cues in the vertical migration behavior of the marine planktonic copepod Acartia hudsonica. J Plankton Res 16:555
Bollner T, Stormmathisen J, Ottersen OP (1991) Gaba-like immunoreactivity in the nervous system of Oikopleura dioica (Appendicularia) Biol Bull 180 :119-124
Bowerman RF, Larimer JL (1976) Command neurons in crustaceans. Comp Biochem Physiol 54A:1-6
Bowlby MR, Case JF (1991) Ultrastructure and neuronal control of luminous cells in the copepod Gaussia princeps. Biol Bull 180:440-446
Boyle MB, Cohen LB, Macagno ER, Orbach H (1983) The number and size of neurons in the CNS of gastropod molluscs and their suitability for optical recording of activity. Brain Res 266:305-317
Budelmann BU (1989) Hydrodynamic receptor systems in invertebrates. In: The Mechanosensory Lateral Line: Neurobiology and Evolution. S Coombs, P Görner, H Munz, eds. Springer-Verlag, New York, pp 607-631
Budelmann BU, Bleckmann H (1988) A lateral line analogue in cephalopods: water waves generate microphonic potentials in the epidermal head lines of Sepia and Lolliguncula. J Comp Physiol A 164:1-5
Budelmann BU, Riese U, Bleckmann H (1991) Structure, function, and biological significance of the cuttlefish "lateral lines". In: The Cuttlefish. E Boucaud-Camou, ed. Centre de Publications de l'Université de Caen, pp 201-209
Bullock TH (1943) Neuromuscular facilitation in Scyphomedusae. J Cell Comp Physiol 22:251-272
Bullock TH (1946) A preparation for the physiological study of the unit synapse. Nature 158:555-556
Bullock TH (1948a) Physiological mapping of giant nerve fiber systems in polychaete annelids. Physiol Comp Oecol 1:1-14
Bullock TH (1948b) Properties of a single synapse in the stellate ganglion of squid. J Neurophysiol 11:343-364
Bullock TH (1953a) Properties of some natural and quasi-artificial synapses in polychaetes. J Comp Neurol 98:37-68
Bullock TH (1953b) Predator recognition and escape responses of some intertidal gastropods in presence of starfish. Behaviour 5:130-140
Bullock TH (1955) Compensation for temperature in the metabolism and activity of poikilotherms. Biol Rev 30:311-341
Bullock TH (1974) An essay on the discovery of sensory receptors and the assignment of their functions together with an introduction to electroreceptors. In: Handbook of Sensory Physiology, Vol. III/3: Electroreceptors and Other Specialized Receptors in Lower Vertebrates. A Fessard, ed. Springer Verlag, Berlin, pp 1-12
Bullock TH, Budelmann BU (1991) Sensory evoked potentials in unanesthetized, unrestrained cuttlefish: a new preparation for brain physiology in cephalopods. J Comp Physiol A 168:141-150
Bullock TH, Corwin JT (1979) Acoustic evoked activity in the brain in sharks. J Comp Physiol 129:223-234
Bullock TH, Hagiwara S (1957) Intracellular recording from the giant synapse of the squid. J Gen Physiol 40:565-577
Bullock TH, Heiligenberg WF (1986) Electroreception. New York, John Wiley
Bullock TH, Hagiwara S, Kusano K, Negishi K (1961) Evidence for a category of electroreceptors in the lateral line of gymnotid fishes. Science 134:1426-1427
Bundy MH, Paffenhofer GAS (1993) Innervation of copepod antennules investigated using laser scanning confocal microscopy. Marine Ecology-Progress Series 102:1-14
Cohen MJ, Katsuki Y, Bullock TH (1953) Oscillographic analysis of equilibrium receptors in crustacea. Experientia 9:434-435
Coombs S, Görner P, Münz H (1989) The Mechanosensory Lateral Line: Neurobiology and Evolution. Springer-Verlag, New York
Cooper KM, Hanlon RT, Budelmann BU (1990) Physiological color change in squid iridophores. II. Ultrastructural mechanisms in Lolliguncula brevis. Cell Tissue Res 259:15-24
Corning WC, Dyal JA, Willows AOD (1973) Invertebrate Learning. Vol 1, Protozoans through Annelids. Plenum Press, New York
Costello JH, Strickler JR, Marrase C, Trager G, et al. (1990) Grazing in a turbulent environment - behavioral response of a calanoid copepod, Centropages hamatus. Proc Natl Acad Sc USA 87:1648-1652
Cronin TW, Marshall NJ, Caldwell RL, Shashar N (1994) Specialization of retinal function in the compound eyes of mantis shrimps. Vision Res 34:2639-2656
Demott WR, Watson MD (1991) Remote detection of algae by copepods - responses to algal size, odors and motility. J Plankton Res 13:1203-1222
Denton EJ, Gray JA (1985) Lateral-line-like antennae of certain of the Penaeidae (Crustacea, Decapoda, Natantia). Proc R Soc Lond B Biol Sci 226:249-261
DeWeile J (1983) Electrosensory information processing by lateral-line lobe neurons of catfish investigated by means of white noise cross-correlation. Comp Biochem Physiol 74A:677-680
Digby PSB (1961) Mechanism of sensitivity to hydrostatic pressure in the prawn, Palaemonetes varians Leach. Nature 191:366-368
Dineen JF, Hines AH (1994) Larval settlement of the polyhaline barnacle Balanus eburneus (Gould) - cue interactions and comparisons with two estuarine congeners. J Exp Mar Biol Ecol 179:223-234
Eaton RC (1984) Neural mechanisms of startle behavior. Plenum, New York, 377 pp
Eaton RC, DiDomenico R (1986) Role of the teleost escape response during development. Trans Am Fish Soc 115:128-142
Eaton RC, Nissanov (1985) A review of Mauthner-initiated escape behavior and its possible role in hatching in the immature zebrafish, Brachydanio rerio. Environmental Biology of Fishes 12:265-279
Eaton RC, Kimmel CB (1980) Directional sensitivity of the Mauthner cell system to vibrational stimulation in zebrafish larvae. J Comp Physiol A 140:337-342
Elkins T, Ganetzky B (1990) Conduction in the giant nerve fiber pathway in temperature-sensitive paralytic mutants of Drosophila. J Neurogenetics 6:207-219.
Engel JE, Wu CF (1992) Interactions of membrane excitability mutations affecting potassium and sodium currents in the flight and giant fiber escape systems of Drosophila. J Comp Physiol A 171:93-104
Enright JT (1962) Responses of an amphipod to pressure changes. Comp Biochem Physiol 7:131-145
Enright JT (1961) Pressure sensitivity of an amphipod. Science 133:758-760
Enright JT (1963) Estimates of the compressibility of some marine crustaceans. Limn Ocean 8:382-387
Enright JT (1967) Temperature compensation in short-duration time-measurement by an intertidal amphipod. Science 156:1510-1512
Evans BI, Harosi FI, Fernald RD (1993) Photoreceptor spectral absorbance in larval and adult winter flounder (Pseudopleuronectes americanus). Visual Neurosci 10:1065-71
Fan S-F, Hsu K, Chen F-S (1961) On the high conduction velocity of the giant nerve fiber of shrimp Penaeus orientalis. Kexue Tongbao 4:51-52
Featherstone D, Drewes CD (1991) Non-invasive detection of electrical events during the startle response in larval medaka. J exp Biol 158:583-589
Fields RD, Bullock TH, Lange GD (1993) Ampullary sense organs, peripheral, central and behavioral electroreception in chimeras (Hydrolagus, Holocephali, Chondrichthyes). Brain Behav Evol 41:269-289
Finger TE, Silver WL (1987) Neurobiology of taste and smell. John Wiley & Sons, New York
Forward RB (1989a) Depth regulation of larval marine decapod crustaceans - test of an hypothesis. Marine Biol 102:195-201
Forward RB (1989b) Behavioral responses of crustacean larvae to rates of salinity change. Biol Bull 176:229-238
Forward RB (1990a) Responses of crustacean larvae to hydrostatic pressure - behavioral basis of high barokinesis. Marine Behav Physiol 17:223-232
Forward RB (1990b) Behavioral responses of crustacean larvae to rates of temperature change. Biol Bull 178:195-204
Forward RB, Buswell CU (1989) A comparative study of behavioural responses of larval decapod crustaceans to light and pressure. Marine Behav Physiol 16:43-56
Foster BA, Cargill JM, Montgomery JC (1987) Planktivory in Pagothenia borchgrevinki (Pisces: Nototheniidae) in McMurdo Sound, Antarctica. Polar Biol 8:49-54
Gibson RM (1983) Visual abilities and foraging behavior of predatory fish. Trends Neurosci 6:197-199
Gilmer RW (1990) In situ observations of feeding behavior of thecosome pteropod molluscs. Am Malacolog Bull 8:53-59
Goto T, Yoshida M (1988) Histochemical demonstration of a rhodopsin-like substance in the eye of the arrowworm Spadella schizoptera Chaetognatha. Exp Biol (Berl) 48:1-4
Goto T, Yoshida M (1983 The role of the eye and central nervous system components in phototaxis of the arrowworm Sagitta crassa. Biol Bull 164:82-92
Goto T, Takasu N, Yoshida M (1984) A unique photo receptive structure in the arrowworms Sagitta crassa and Spadella schizoptera Chaetognatha. Cell Tissue Res 235:471-478
Greve W (1975) Verhaltensweisen der Rippenquallen Pleurobrachia pileus (Ctenophora). Inst Wissenschaftlichen Film. Wissenschaftlicher Film C 1181/1975. Göttingen
Gwilliam GF (1963) The mechanism of the shadow reflex in Cirripedia I. Biol Bull 125:470-485
Hanlon RT, Hixon RF, Hulet WH (1978) Laboratory maintenance of wild-caught loliginid squids. In: Proceedings of the Workshop on the Squid Illex illecebrosus. N Balch, T Amaratunga, RK O'Dor, eds. Fisheries and Marine Service, Halifax, Nova Scotia
Hanlon RT, Hixon RF, Hulet WH (1983) Survival, growth, and behavior of the loliginid squid Loligo plei, Loligo pealei, and Lolliguncula brevis (Mollusca: Cephalopoda) in closed sea water systems. Biol Bull 165:637-685
Hanlon RT, Cooper KM, Budelmann BU, Pappas TC (1990) Physiological color change in squid iridophores. I. Behavior, morphology and pharmacology in Lolliguncula brevis. Cell Tissue Res 259:3-14
Hao B, Hsu K (1965) The birefringence properties of the myelin sheath of shrimp nerve fiber. Acta Physiol Sin 28:373-377.
Hardy AC, Bainbridge R (1951) Effect of pressure on the behavior of decapod larvae (Crustacea). Nature 167:354-355
Hartline PH, Lange GD (1974) Optic nerve responses to visual stimuli in squid. J Comp Physiol 93:37-54
Harvey AW (1993) Larval settlement and metamorphosis in the sand crab Emerita talpoida (Crustacea, Decapoda, Anomura). Mar Biol 117:575-581
Hayashi I, Yamane S (1994) On a probable sense organ newly found in some eunicid polychaetes. J Mar Biol Assoc UK 74:765
Head EJH, Harris LR (1994) Feeding selectivity by copepods grazing on natural mixtures of phytoplankton determined by Hplc analysis of pigments. Marine Ecology-Progress Series 110:75-83
Holmes W, Pumphrey RJ, Young JZ (1941) The structure and conduction velocity of the medullated nerve fibres of prawns. J Exp Biol 18:50-54
Horridge GA (1953) An action potential from the motor nerves of the jellyfish, Aurellia aurita Lamarck. Nature (Lond) 171:400
Hough AR, Naylor E (1992) Endogenous rhythms of circatidal swimming activity in the estuarine copepod Eurytemora affinis (Poppe) J Exp Mar Biol Ecol 161:27-32
Hsu K (1982) Structural and functional characteristics of nerve fibers of shrimp Penaeus orientalis. IBRO News 10:10-11
Hsu K, Tan T-P, Chen F-S (1964) On the excitation and saltatory conduction of giant fiber of shrimp (Penaeus orientalis). In: Theses of the 14th National Congress of Chinese Association of Physiologists
Hsu K, Tan T-P, Chen F-S (1975a) Saltatory conduction in the myelinated giant fibre of the shrimp (Penaeus orientalis). Kexue Tongbao 20:380-382
Hsu K, Yang Q-Z, Tsou S-H (1975b) On the apparent lack of resting membrane potential in the shrimp giant nerve fibre. Kexue Tongbao 20:383-386
Huang S-K, Yeh YH, K (1963) A microscopic and electron microscopic investigation of the myelin sheath of the nerve fiber of Penaeus orientalis. Acta Physiol Sin 26:39-42
Huang Z, Satterlie RA (1990) Neuronal mechanisms underlying behavioral switching in a pteropod mollusc. J Comp Physiol A 166:875-887
Irisawa H, Irisawa AF, Matsubayashi T, Kobayashi M (1962) The nervous control of the intracellular action potential of the Squilla heart. J Cell Comp Physiol 59:55-60
Ishii H (1990) In situ feeding rhythms of herbivorous copepods, and the effect of starvation. Mar Biol 105:91-98
Iversen RTB (1967) Response of yellowfin tuna (Thunnus albacares) to underwater sound. In: Marine Bio-acoustics, Vol 2. WM Tavolga, ed. Pergamon Press, Oxford
Jensen PG, Moyse J, Hoeg J, Alyahya H (1994) Comparative SEM studies of lattice organs - putative sensory structures on the carapace of larvae from Ascothoracida and Cirripedia (Crustacea Maxillopoda Thecostraca). Acta Zool 75:125-142
Johnson LE, Strathmann RR (1989) Settling barnacle larvae avoid substrata previously occupied by a mobile predator. J Exp Mar Biol Ecol 128:87-103
Jonsson PR, Tiselius P (1990) Feeding behaviour, prey detection and capture efficiency of the copepod Acartia tonsa feeding on planktonic ciliates. Marine Ecology-Progress Series 60:35-44
Jordan CE (1992) A model of rapid-start swimming at intermediate Reynolds number - undulatory locomotion in the chaetognath Sagitta elegans. J Exp Biol 163:119-137
Kabotyanski EA, Sakharov DA (1988) Monoamine-dependent behavioural states in the pteropod mollusc Clione limacina. Symp Biol Hung 36:463-477
Kabotyanskii EA, Sakharov DA (1989) Catecholaminergic neurons of the pteropod mollusc Clione limacina. J Evol Biochemi Physiol 25:198-207
Kalmijn AJ (1988a) Hydrodynamic and acoustic field detection. In: Sensory Biology of Aquatic Animals. J Atema, RR Fay, WN Tavolga, eds. Springer Verlag, New York, pp 83-130
Kalmijn AJ (1988b) Detection of weak electric fields. In: Sensory Biology of Aquatic Animals. J Atema, RR Fay, AN Popper, WN Tavolga, eds. Springer Verlag, New York, pp 151-186
Kalmijn AJ, Blakemore RP (1978) The magnetic behavior of mud bacteria. In: Animal Migration, Navigation and Homing. L Schmidt-Koenig, WT Keeton, eds. Springer Verlag, New York, pp 354-355
Kassimon G, Hufnagel LA (1992) Suspected chemoreceptors in coelenterates and ctenophores. Micros Res Tech 22:265-284
Kawabata K (1991) Ontogenetic changes in copepod behaviour - an ambush cyclopoid predator and a calanoid prey. J Plankton Res 13:27-34
Kerfoot WC, Kirk KL (1991) Degree of taste discrimination among suspension-feeding cladocerans and copepods - implications for detritivory and herbivory. Limnol Oceanog 36:1107-1123
King DG (1976) Organization of crustacean neuropil. I. Patterns of synaptic connections in lobster stomatogastric ganglion. J Neurocytol 5:207-237
Knight-Jones EW, Qasim SZ (1955) Responses of some marine plankton animals to changes in hydrostatic pressure. Nature 175:941-942
Kotrschal K, Adam H. Brandstatter R, Junger H, Zaunreiter M, Goldschmid A (1990) Larval size constraints determine directional ontogenetic shifts in the visual system of teleosts. A mini-review. Z Zool Syst Evolutionsforsch 28:166-182
Krishnan SN, Frei E, Swain GP, Wyman RJ (1993) Passover - a gene required for synaptic connectivity in the giant fiber system of Drosophila. Cell 73:967-977.
Kurihara K, Suzuki N, Ogawa H (1994) Olfaction and Taste XI. Springer Verlag, New York, 700 pp
Kusano K (1965) Electrical characteristics and fine structure of the Kuruma-shrimp nerve fibres (Penaeus japonicus). Proc Jpn Acad 41:952-957
Kusano K (1966) Electrical activity and structural correlates of giant fibers in Kuruma shrimp (Penaeus japonicus). J Cell Physiol 68:361-384
Kusano K (1971) Impulse conduction in the shrimp medullated giant fiber with special reference to the structure of functionally excitable areas. J Comp Neurol 142:481-494
Lange GD, Hartline PH (1974) Retinal responses in squid and octopus. J Comp Physiol 93:19-36
Lange GD, Hartline PH, Hurley AC (1979) Retinal responses in Nautilus. J Comp Physiol 134:281-285
Larson RJ (1986) Studies on the fauna of Curacao and other Caribbean Islands No. 213. Observations on the light-inhibited activity cycle and feeding behavior of the hydromedusa Olindias tenuis. Uitg Natuurwet Studiekring Suriname Ned Antillen 0 (118):191-199
Latz MI, Bowlby MR, Case JF (1990) Recovery and stimulation of copepod bioluminescence. J Exp Mar Biol Ecol 136:1-22
Laverack MS (1980) Electrophysiology of the isolated central nervous system of the northern octopus Eledone cirrhosa. Mar Behav Physiol 7:155-169.
Laverack MS, Sinclair A (1994) Innervation of the dorsal organ of the shrimp Macrobrachium intermedium (Decapoda, Natantia). J Crust Biol 14:1-5
Lazzaretto I, Salvato B, Libertini A (1990) Evidence of chemical signalling in Tigriopus fulvus (Copepoda, Harpacticoida). Crustaceana 59:171-179
Lenz PH, Yen J (1993) Distal setal mechanoreceptors of the 1st antennae of marine copepods. Bull Mar Sci 53:170-179
Lenz PH, Weatherby TM, Weber W, Wong KK (1995) Sensory specialization along the first antenna of a calanoid copepod, Pleuromamma xiphias (Crustacea). This volume.
Lohmann KJ, Willows AOD, Pinter RB (1991) An identifiable molluscan neuron responds to changes in earth-strength magnetic fields. J Exp Biol 161:1-24
Mackie GO (1984) Fast pathways and escape behavior in Cnidaria. In: Neural Mechanisms of Startle Behavior. RC Eaton, ed. Plenum, New York, pp 15-42
Mackie GO (1990) Giant axons and control of jetting in the squid Loligo and the jellyfish Aglantha. Can J Zool 68:799-805
MacNichol EFJ, Love WE (1960a) Electrical responses of the retinal nerve and optic ganglion of the squid. Science 132:737-738
MacNichol EFJ, Love WE (1960b) Impulse discharges from retinal nerve and optic ganglion of the squid. In: Symposium on the Visual System. R Jung, J Kornhuber, eds. Springer, Heidelberg, pp 97-103
Marsden JR (1990) Light responses of the planktotrophic larva of the serpulid polychaete Spirobranchus polycerus. Mar Ecol Prog Ser 58:225-234
Matsumoto GI, Harbison GR (1993) In situ observations of foraging, feeding, and escape behavior in three orders of oceanic ctenophores - Lobata, Cestida, and Beroida. Mar Biol 117:279-287
Maturana HR, Sperling S (1963) Unidirectional response to angular acceleration recorded from the middle cristal nerve in the statocyst of Octopus vulgaris. Nature (Lond) 197:815-816
McClintock JB, Janssen J (1990) Pteropod abduction as a chemical defence in a pelagic antarctic amphipod. Nature 346:462-464
Montgomery JC, Macdonald JA, Housley GD (1988) Lateral line function in an antarctic fish related to the signals produced by planctonic prey. J Comp Physiol A 163:827-833
Morgan E (1984) The pressure-responses of marine invertebrates: a psychophysical perspective. Zool J Linn Soc 80:209-230
Moss AG, Tamm SL (1993) Patterns of electrical activity in comb plates of feeding Pleurobrachia (Ctenophora). Philos Trans R Soc Lond B Biol Sci 339:1-16
Moynihan M, Rodaniche AF (1982) The Behavior and Natural History of the Caribbean Reef Squid Sepioteuthis sepioidea. Verlag Paul Parey, Berlin
Mpitsos GJ, Lukowiak K (1985) Learning in gastropod molluscs. In: The Mollusca, Vol 8, Neurobiology and Behavior, Part 1. AOD Willows, ed. Academic Press, pp 95-267
Munz SW, McFarland WN (1977) Evolutionary adaptations of fishes to the photic environment. In: Handbook of Sensory Physiology, H.J. Autrum, ed., vol. VII/5 Visual System in Vertebrates. F. Crescitelli, ed. Springer-Verlag, New York pp.193-274.
Newbury TK (1972) Vibration perception by chaetognaths. Nature 236:459-460
Nicol JAC (1960) The regulation of light emission in animals. Biol Rev 35:1-42
Nilsson D-E (1983) Evolutionary links between apposition and superposition optics in crustacean eyes. Nature (Lond) 302: 818-821
Norekyan TP (1989) Neurons determining passive defensive response in the pteropod mollusk Clione limacina. Neurophysiology 21:495-502
Norekian TP (1993) Cerebral neurons underlying prey capture movements in the pteropod mollusc, Clione limacina. 2. Afterdischarges. J Comp Physiol A 172:171-181
Norekian TP, Satterlie RA (1993a) Co-activation of antagonistic motoneurons as a mechanism of high-speed hydraulic inflation of prey capture appendages in the pteropod mollusk Clione limacina. Biol Bull 185:240-247
Norekian TP, Satterlie RA (1993b) Cerebral neurons underlying prey capture movements in the pteropod mollusc, Clione limacina. 1. Physiology, morphology. J Comp Physiol A 172:153-169
Norekian TP, Satterlie RA (1994) Small cardioactive peptide B increases the responsiveness of the neural system underlying prey capture reactions in the pteropod mollusc, Clione limacina. J Exp Zool 270:136-147
Novicki A, Budelmann BU, Hanlon RT (1990) Brain pathways of the chromatophore system in the squid. Brain Res 519:315-323
Ogmen H, Garnier L (1994) Quantitative studies of fly visual sustained neurons. Internat J Bio-Med Computing 36:299-310
Ogura T, Obara S (1992) The membrane properties and Ca-currents of the trigeminal root ganglion cells in primary culture of the marine catfish, Plotosus, studied with whole-cell recordings. Brain Res 597:84-91
Olsson R, Holmberg K, Lilliemarck Y (1990) Fine structure of the brain and brain nerves of Oikopleura dioica (Urochordata, Appendicularia). Zoomorphology 110:1-7
Otis TS, Gilly WF (1990) Jet-propelled escape in the squid Loligo opalescens: concerted control by giant and non-giant motor axon pathways. Proc Natl Acad Sci USA 87:2911-2915
Paffenhofer GA, Lewis KD (1990) Perceptive performance and feeding behavior of calanoid copepods. J Plankton Res 12:933-946
Page LR (1993) Development of behaviour in juveniles of Melibe leonina (Gastropoda, Nudibranchia). Mar Behav Physiol 22:141-161
Partridge BL, Pitcher TJ (1980) The sensory basis of fish schools:relative roles of lateral line and vision. J Comp Physiol A 135:315-325
Paul DH (1981a) Homologies between body movements and muscular contractions in the locomotion of two decapods of different families. J Exp Biol 94:159-168
Paul DH (1981b) Homologies between neuromuscular systems serving different functions in two decapods of different families. J Exp Biol 94:169-187
Paul DH (1989) A neurophylogenist's view of decapod crustacea. Bull Mar Sci 45:487-504
Paulus U, Kortje KH, Rahmann H (1993) Effects of development and altered Gravity conditions on cytochrome oxidase activity in a vestibular nucleus of the larval teleost brain - a quantitative electronmicroscopical study. J Neurobiol 24:1131-1141
Poulin R, Curtis MA, Rau ME (1990) Responses of the fish ectoparasite Salmincola edwardsii (Copepoda) to stimulation, and their implication for host-finding. Parasitology 100:417-421
Prokopy R, Bergweiler C, Galarza J, Schwerin J (1994) Prior experience affects the visual ability of Rhagoletis pomonella flies (Dipotera, Tephritidae) to find host fruit. J Insect Behav 7:663-677
Przysiezniak J, Spencer AN (1989) Primary culture of identified neurons from a cnidarian. J Exp Biol 142:97-113
Ryland JS (1990) A circadian rhythm in the tropical ascidian Diplosoma virens (Ascidiacea, Didemnidae) J Exp Mar Biol Ecol 138:217-225
Saidel WM (1980) Orthogonal polarization sensitivities of squid photoreceptors: implication for a retinal design. Biol Bull 159:490
Saidel WM, Lettvin JY, MacNichol EF, Jr. (1983) Processing of polarized light by squid photoreceptors. Nature 304:534-536
Sand A (1938) The function of the ampullae of Lorenzini, with some observations on the effect of temperature of sensory rhythms. Proc R Soc Lond B Biol Sci 125:524-533
Sandeman DC, Atwood HL (1982) Neural integration and behavior. Vol. 4 of The Biology of Crustacea, DE Bliss, ed. Academic Press, New York, 327 pp. (Several relevant chapters.)
Satterlie RA (1993) Neuromuscular organization in the swimming system of the pteropod mollusc Clione limacina. J Exp Biol 181:119-140
Saunders AJ, Montgomery JC (1985) Field and laboratory studies of the feeding behavior of piper Hyporhamphus ihi with reference to the role of the lateral-line in feeding. Proc R Soc Lond B Biol Sci 224:209-222
Schiff H (1987) Optical and neural pooling in visual processing in Crustacea. Comp Biochem Physiol 88A:1-13
Schiff H (1989) Visual input patterns correlated to behavior and habitat of the mantis shrimp Gonodactylus. Comp Biochem Physiol 94A:75-87
Sejnowski TJ, Reingold SC, Kelley DB, Gelperin A (1980) Localization of [3H]-2-deoxyglucose in single molluscan neurones. Nature 287:449-451
Sensenbaugh T, Franzen A (1987) Fine structural observations of the apical organ in the larva of Polygordius annelida polychaeta. Scanning Microsc 1:181-190
Sherman RG, Atwood HL (1972) Correlated electrophysiological and ultrastructural studies of a crustacean motor unit. J Gen Physiol 59:586-615
Smith KC, Macagno ER (1990) UV photoreceptors in the compound eye of Daphnia magna (Crustacea, Branchiopoda). A fourth spectral class in single ommatidia. J Comp Physiol A 166:597-606
Snell TW, Morris PD (1993) Sexual communication in copepods and rotifers. Hydrobiologia 255:109-116
Späth M (1978) First central processing of temperature in teleost fish. Verh Deutsch Zool Ges 1978:210
Spencer AN (1988) Non-spiking interneurons in the pedal ganglia of a swimming mollusc. J Exp Biol 134:442-450
Sumida BH, Case JF (1983) Food recognition by Chaetopterus variopedatus. Synergy of mechanical and chemical stimulation. Mar Behav Physiol 9:249-274
Sweatt AJ (1985) Rod outer segment-like structure of an invertebrate photoreceptor, Phylum Chaetognatha. J Cell Biol 101:222A
Sweatt AJ, Forward RB Jr (1985) Spectral sensitivity of the chaetognath Sagitta hispida. Biol Bull 168:32-38
Tamm S, Tamm S (1991) Actin pegs and ultrastructure of presumed sensory receptors of Beroe (Ctenophora). Cell Tissue Res 264:151-159
Terakawa S, Hsu K (1991) Ionic currents of the nodal membrane underlying the fastest saltatory conduction in myelinated giant nerve fibers of the shrimp Penaeus japonicus. J Neurobiol 22:342-352
Theisen B, Zeiske E, Silver WL, Marui T, et al. (1991) Morphological and physiological studies on the olfactory organ of the Striped Eel Catfish, Plotosus lineatus. Mar Biol 110:127-135
Therman PO (1940) The action potentials of the squid eye. Am J Physiol 130:239-248
Trapido-Rosenthal HG, Morse DE (1986) Availability of chemosensory receptors is down-regulated by habituation of larvae to a morphogenetic signal. Proc Natl Acad Sci USA 83:7658-7662
Trimarchi JR, Schneiderman AM (1993) Giant fiber activation of an intrinsic muscle in the mesothoracic leg of Drosophila melanogaster. J Exp Biol 177:149-167
Trimarchi J, Watson WH (1992) The role of the Melibe buccal ganglia in feeding behavior. Mar Behav Physiol 19:195-209
Viancour TA (1979) Peripheral electrosense physiology: a review of recent findings. J Physiol (Paris) 75:321-333
Waterman TH, Wiersma CAG (1963) Electrical responses in decapod crustacean visual systems. J Cell Comp Physiol 61:1-16
Watson WH, Chester CM (1993) The influence of olfactory and tactile stimuli on the feeding behavior of Melibe leonina (Gould, 1852) (Opisthobranchia, Dendronotacea). Veliger 36:311-316
Watson WH, Trimarchi J (1992) A quantitative description of Melibe feeding behavior and its modification by prey density. Mar Behav Physiol 19:183-194
Welsford IG, Meyers RA, Wilson DS, Satterlie RA et al. (1991) Neuromuscular organization for wing control in a mollusc (Clione limacina) and a bird (Columba livia) - parallels in design. Am Zool 31:670-679
Wiese K, Marschall H-P (1990) Sensitivity to vibration and turbulence of water in context with schooling in Antarctic krill, Euphausia superba. In: Frontiers in Crustacean Neurobiology. K Wiese, W-D Krenz, J Tautz, H Reichert, B Mulloney, eds. Birkhäuser, Boston, pp 121-130
Wiese K, Krenz W-D, Tautz J, Reichert H, Mulloney B (1990) Frontiers in Crustacean Neurobiology. Birkhäuser, Boston. (Several relevant chapters.)
Wiersma CAG, Hirsh R (1974) Memory evoked optomotor responses in crustaceans. J Neurobiol 5:213-230
Wiersma CAG, Van Harreveld A (1938) A comparative study of the double motor innervation in marine crustaceans. J Exp Biol 15:18-31
Wiersma CAG, Waterman TH, Bush BMH (1961) The impulse traffic in the optic nerve of decapod crustacea. Science 134:1435
Williamson R (1989) Electrical coupling between secondary hair cells in the statocyst of the squid Alloteuthis subulata. Brain Res 486:67-72
Willows AOD, Hoyle G (1969) Neuronal network triggering a fixed action pattern. Science 166:1549-1551
Wilson DM (1959) Long-term facilitation in a swimming sea anemone. J Exp Biol 36:526-532
Wilson DM (1960) Nervous control of movement in annelids. J Exp Biol 37:46-56
Wilson LJ, Paul DH (1987) Tailflipping of Munida quadrispina (Galatheidae): conservation of behavior and underlying musculature with loss of anterior contralateral flexor motoneurons and motor giant. J Comp Physiol A 161:881-890
Wyman RJ, Thomas JB, Salkoff L, King DG (1984) The Drosophila giant fiber system. In: Neural Mechanisms of Startle Behavior. RC Eaton, ed. Plenum, New York, pp 133-162
Yen J, Lenz PH, Gassie DV, Hartline DK (1992) Mechanoreception in marine copepods - electrophysiological studies on the first antennae. J Plankton Res 14:495-512
Zakharov IS, Ierusalimsky VN (1992) The neuroanatomical basis of feeding behavior in the pteropod mollusc, Clione limacina (Phipps). J Comp Physiol A 170:525-532