Mather, Jennifer

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    Behaviour development: a cephalopod perspective
    (University of California eScholarship, 2006) Mather, Jennifer A.
    This paper evaluates the development of behaviour from the viewpoint of the intelligent and learning dependent cephalopod mollusks as a contrast to that of mammals. They have a short lifespan, commonly one to two years, and most are semelparous, reproducing only near the end of their lifespan. In the first two months of life, Sepia officinalis cuttlefish show drastic limitation on learning of prey choice and capture, gradually acquiring first short-term and then long-term learning over 60 days. This is paralleled by development of the vertical lobe of the brain which processes visually learned information. In the long nonreproductive adulthood, Octopus species show major flexibility in prey choice and continued mobility across the sea bottom. This results in large behaviour variability within and between individuals and both exploration and simple play-type behaviour. During the short reproductive period, Sepioteuthis sepioidea squid gather for choice and competition, including flexible strategies in use of their skin display system. At the end of the life cycle, Sepia officinalis cuttlefish have a swift decline in memory capacity and also brain degeneration during their short period of senescence. The emphasis on different behaviour capacities during these four stages is contrasted with those of the mammalian model of behaviour development.
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    Ethics and invertebrates: a cephalopod perspective
    (Inter Research, 2007) Mather, Jennifer A.; Anderson, Roland C.
    This paper first explores 3 philosophical bases for attitudes to invertebrates, Contractarian/Kantian, Utilitarian, and Rights-based, and what they lead us to conclude about how we use and care for these animals. We next discuss the problems of evaluating pain and suffering in invertebrates, pointing out that physiological responses to stress are widely similar across the animal kingdom and that most animals show behavioral responses to potentially painful stimuli. Since cephalopods are often used as a test group for consideration of pain, distress and proper conditions for captivity and handling, we evaluate their behavioral and cognitive capacities. Given these capacities, we then discuss practical issues: minimization of their pain and suffering during harvesting for food; ensuring that captive cephalopods are properly cared for, stimulated and allowed to live as full a life as possible; and, lastly, working for their conservation.
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    Exploration and habituation in intact free moving Octopus vulgaris
    (University of California eScholarship, 2006) Kuba, Michael J.; Byrne, Ruth A.; Meisel, Daniela V.; Mather, Jennifer A.
    Despite the huge numbers of studies published on the learning of cephalopod mollusks, studies on non-associative learning are scarce. We tested non-associative learning (habituation) and exploration in Octopus vulgaris in two different studies using a prey-shaped object (Study A) and inanimate objects and food objects (Study B). Study A consisted of the repeated presentation of a prey-like stimulus, which 23 subjects could only explore visually. In study B, 14 octopuses were presented two Lego blocks (one black and white with a smooth surface, one a blue "snowflake" with a rough surface) and two food items, one preferred (clams) and one non-preferred (mussels) inside their home tanks. As hunger is a motivational factor for exploratory behavior, different levels of food satiation (feeding 2h or 24 h prior to experiments) were tested. Within trial habituation was clearly documented in both experiments. In study A across trials habituation was found for all animals, whereas it was only significant in 5 animals in Study B.
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    Geographic variability of Octopus insularis diet: from oceanic island to continental populations
    (Inter Research, 2016) Leite, Tatiana S.; Batista, Allan T.; Lima, Francoise D.; Barbosa, Jaciana C.; Mather, Jennifer
    A predator’s choice of prey can be affected by many factors. We evaluated various influences on population dietary composition, individual specialization and size of prey in Octopus insularis populations from 2 continental and 4 insular locations. We expected that habitat diversity would lead to diet heterogeneity. Furthermore, in keeping with MacArthur & Wilson’s (1967) theory of island biogeography, we expected that diet diversity would be lower around islands than on the coast of the mainland. Both predictions were confirmed when prey remains from octopus middens were examined. The 2 continental areas exhibited a richer habitat diversity and a wider variety of prey. Niche widths in the continental areas were 2.42 and 2.03, with the lowest niche widths exhibited by the population from the most distant oceanic islands (1.30, 0.85). We found variation in the proportion of specialist relative to generalist individuals across areas based on the proportional similarity index. The correlation between habitat diversity and niche width (R2 = 0.84) was highly significant, as was distance from the continental shelf and niche width (R2 = 0.89). This study reaffirms the central position of octopuses in the nearshore benthic ecosystem, and supports MacArthur & Wilson’s (1967) prediction of a lower diversity of species on islands—which applies not only to the species themselves, but also indirectly for the diet of their predators.
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    Individual prey choices of octopuses: are they generalist or specialist?
    (Oxford University Press, 2012) Mather, Jennifer A.; Leite, Tatiana S.; Batista, Allan T.
    Prey choice is often evaluated at the species or population level. Here, we analyzed the diet of octopuses of different populations with the aim to assess the importance of individual feeding habits as a factor affecting prey choice. Two methods were used, an assessment of the extent to which an individual octopus made choices of species representative of those population (PSi and IS) and 25% cutoff values for number of choices and percentage intake of individual on their prey. In one population of Octopus cf vulgaris in Bermuda individuals were generalist by IS=0.77, but most chose many prey of the same species, and were specialists on it by >75% intake. Another population had a wider prey selection, still generalist with PSi=0.66, but two individuals specialized by choices. In Bonaire, there was a wide range of prey species chosen, and the population was specialists by IS= 0.42. Individual choices revealed seven specialists and four generalists. A population of Octopus cyanea in Hawaii all had similar choices of crustaceans, so the population was generalist by IS with 0.74. But by individual choices, three were considered a specialist. A population of Enteroctopus dofleini from Puget Sound had a wide range of preferences, in which seven were also specialists, IS=0.53. By individual choices, thirteen were also specialists. Given the octopus specialty of learning during foraging, we hypothesize that both localized prey availability and individual personality differences could influence the exploration for prey and this translates into different prey choices across individuals and populations showed in this study
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    Marine invertebrates: communities at risk
    (M D P I A G, 2013) Mather, Jennifer
    Our definition of the word 'animal' centers on vertebrates, yet 99% of the animals on the planet are invertebrates, about which we know little. In addition, although the Census of Marine Life (COML.org) has recently conducted an extensive audit of marine ecosystems, we still do not understand much about the animals of the seas. Surveys of the best-known ecosystems, in which invertebrate populations often play a key role, show that the invertebrate populations are affected by human impact. Coral animals are the foundation of coral reef systems, which are estimated to contain 30% of the species in the ocean. Physical impact and chemical changes on the water severely damage these reefs, and may lead to the removal of these important habitats. Tiny pteropod molluscs live in huge numbers in the polar seas, and their fragile shells are particularly vulnerable to ocean acidification. Their removal would mean that fishes on which we depend would have a hugely diminished food supply. In the North Sea, warming is leading to replacement of colder water copepods by warmer water species which contain less fat. This is having an effect on the birds which eat them, who enrich the otherwise poor land on which they nest. Conversely, the warming of the water and the loss of top predators such as whales and sharks has led to an explosion of the jumbo squid of the Pacific coast of North America. This is positive in the development of a squid fishery, yet negative because the squid eat fish that have been the mainstay of the fishery along that coast. These examples show how invertebrates are key in the oceans, and what might happen when global changes impact them.
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    Octopus consciousness: the role of perceptual richness
    (MDPI, 2021) Mather, Jennifer
    It is always difficult to even advance possible dimensions of consciousness, but Birch et al., 2020 have suggested four possible dimensions and this review discusses the first, perceptual richness, with relation to octopuses. They advance acuity, bandwidth, and categorization power as possible components. It is first necessary to realize that sensory richness does not automatically lead to perceptual richness and this capacity may not be accessed by consciousness. Octopuses do not discriminate light wavelength frequency (color) but rather its plane of polarization, a dimension that we do not understand. Their eyes are laterally placed on the head, leading to monocular vision and head movements that give a sequential rather than simultaneous view of items, possibly consciously planned. Details of control of the rich sensorimotor system of the arms, with 3/5 of the neurons of the nervous system, may normally not be accessed to the brain and thus to consciousness. The chromatophore-based skin appearance system is likely open loop, and not available to the octopus’ vision. Conversely, in a laboratory situation that is not ecologically valid for the octopus, learning about shapes and extents of visual figures was extensive and flexible, likely consciously planned. Similarly, octopuses’ local place in and navigation around space can be guided by light polarization plane and visual landmark location and is learned and monitored. The complex array of chemical cues delivered by water and on surfaces does not fit neatly into the components above and has barely been tested but might easily be described as perceptually rich. The octopus’ curiosity and drive to investigate and gain more information may mean that, apart from richness of any stimulus situation, they are consciously driven to seek out more information. This review suggests that cephalopods may not have a similar type of intelligence as the ‘higher’ vertebrates, they may not have similar dimensions or contents of consciousness, but that such a capacity is present nevertheless.
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    Octopus vulgaris in the Caribbean is a specializing generalist
    (Inter Research, 2008) Anderson, Roland C.; Wood, James B.; Mather, Jennifer A.
    The diet of Octopus vulgaris was determined from the remains of 649 prey items gathered from the middens of 38 dens in a small area off the Caribbean island of Bonaire. Remains of 35 species of gastropod (19% of the total), 19 bivalves (51%) and 21 crustaceans (30%) were identified and examined for mode of entry into hard-shelled prey. Although 60% of the gastropods were drilled, neither the size/weight ratio nor the presence of an operculum determined whether drilling occurred. There were strong differences in prey preference among individual octopuses, and the Cardona niche breadth index (B’) of the midden items was 0.08, indicative of specialization. Examples include the exclusive preference for Pinna carnea by one den occupant. This study, by focusing on assessment of preference at specific den locations, is the first to show that while the population had a wide choice of prey items, the individual choices were much narrower, indicating that octopuses were specializing generalists.
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    Reflection: teaching a non-course
    (Kwantlen Polytechnic University, 2008) Mather, Jennifer A.
    A year ago (Spring, 2007), I was on sabbatical. Being on sabbatical means focusing on my intellectual development rather than that of my students. That also means not teaching courses, but I had been teaching...a non-course. This small paper is a reflection on the experience
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    What do professors want to learn to improve their teaching
    (University of Windsor, 2009) Mather, Jennifer A.
    This paper recounts the author’s experience with giving a Needs Assessment for improvement by university teachers. Subjects were from the University of Lethbridge and the 2008 Society for Teaching and Learning in Higher Education (STLHE) conference session. Teachers at the University (n=77) indicated they could spend 5-15 hours in teaching development per semester and wanted a variety of information access but favoured quick one-hour workshops. STLHE participants (n=34) were willing to attend three-hour workshops and spend more time per semester (over 20 hours) improving their teaching. Topics that both groups wanted to hear about were teaching efficiently, using student feedback, fostering critical thinking, and marking fairly. STLHE participants were more interested in fostering group work, student writing, and dealing with student disabilities and diversity, whereas the University sample cared more about preventing cheating and presenting the results of their teaching for promotion and tenure. All in all, there were many things that teachers wanted to learn.
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    Why are octopuses going to be the 'poster child' for invertebrate welfare?
    (Taylor & Francis, 2022) Mather, Jennifer
    Animal welfare consideration and actions are generally addressed to animals similar to us, predominantly large mammals. Invertebrates are neglected partly because they are unknown, though new exploration of the oceans has helped with this. Also, we know little about their ecology and welfare. This is gradually changing, and the octopuses are likely to be the first beneficiaries. Scientists are finding that cephalopods are far more intelligent than we thought, with the Cambridge Declaration of Consciousness suggesting they might possess this quality of mind. Partly as a result, the European Union has described and demanded good care for cephalopods such as the octopus in captivity. Public opinion has been swayed to approval by anecdotes of octopuses doing unusual actions, and by several recent books pointing out interesting and intelligent behavior of cephalopods. Aquariums have begun to feature octopuses for them. With this progress, welfare of invertebrate animals has begun to matter. While the octopuses will be the first animal group to benefit, they may pave the way for us to see that different does not mean unworthy of regard and welfare consideration.