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• 1. [Article] Infection of smallmouth bass and goldfish by two species of Saprolegnia

  This study consisted of several experiments designed to compare the ability of two species of fungi, Saprolegnia ferax and S. parasitica to grow on two species of fish, smallmouth bass (Micropterus dolomieui) ...

  Citation × Citation Citation Abstract Copy Title: Infection of smallmouth bass and goldfish by two species of Saprolegnia Author: McGinley, Cheryl A. Year: 1974 This study consisted of several experiments designed to compare the ability of two species of fungi, Saprolegnia ferax and S. parasitica to grow on two species of fish, smallmouth bass (Micropterus dolomieui) and goldfish (Carassius auratus), and to determine the criteria necessary for the development of these infections. The results indicate that water in the fish tanks must be slightly acid (pH 6), warm (22°C), nonmoving, and that the fish must be wounded in order for fungal infection to occur. Cool water (18°C) and moving water, caused by aeration and filtration, are detrimental to fungal colony formation so that no infection occurs. Both S. ferax and S. parasitica infected both species of fish, on an average of three days after innoculation. The S. ferax infected a higher percentage of both fishes than did the S. parasitica. The difference in susceptibility of the two fish species to the fungi was negligible. Title: Infection of smallmouth bass and goldfish by two species of Saprolegnia Author: McGinley, Cheryl A. Year: 1974 This study consisted of several experiments designed to compare the ability of two species of fungi, Saprolegnia ferax and S. parasitica to grow on two species of fish, smallmouth bass (Micropterus dolomieui) and goldfish (Carassius auratus), and to determine the criteria necessary for the development of these infections. The results indicate that water in the fish tanks must be slightly acid (pH 6), warm (22°C), nonmoving, and that the fish must be wounded in order for fungal infection to occur. Cool water (18°C) and moving water, caused by aeration and filtration, are detrimental to fungal colony formation so that no infection occurs. Both S. ferax and S. parasitica infected both species of fish, on an average of three days after innoculation. The S. ferax infected a higher percentage of both fishes than did the S. parasitica. The difference in susceptibility of the two fish species to the fungi was negligible. Close

• 2. [Article] CCAAT/Enhancer-Binding Protein Delta (C/EBP-delta) Expression in Antarctic Fishes: Implications for Cell Cycle and Apoptosis

  Chapter 1: Antarctic fishes are extremely cold adapted. Despite their inability to upregulate heat shock proteins, recent studies have demonstrated a capacity for heat response in these animals. A cDNA ...

  Citation × Citation Citation Abstract Copy Title: CCAAT/Enhancer-Binding Protein Delta (C/EBP-delta) Expression in Antarctic Fishes: Implications for Cell Cycle and Apoptosis Author: Sleadd, Isaac Martin Year: 2013 Chapter 1: Antarctic fishes are extremely cold adapted. Despite their inability to upregulate heat shock proteins, recent studies have demonstrated a capacity for heat response in these animals. A cDNA microarray study looked at the Notothenioid fish Trematomus bernacchii and revealed heat sensitivities for hundreds of genes, two of which code for members of the CCAAT/Enhancer-binding protein (C/EBP) family of transcription factors. These molecular switches are best known for their roles in apoptosis, inflammation and cell cycle arrest. This dissertation further elucidates the role of C/EBP-delta in the Antarctic fishes T. bernacchii and Pagothenia borchgrevinki. Chapter 2: C/EBP-delta is constitutively expressed in unstressed, field-acclimated (ca. -1.86°C) animals in a highly tissue-specific manner. White muscle tissue contains the highest C/EBP-delta concentration, which is further increased in response to sublethal heat stress at 2.0 or 4.0°C. This response is mostly acute and transitory, but a lesser upregulation was observed in fishes held for one month at 4.0°C. Chapter 3: The heat-induced nuclear translocation of C/EBP-delta--as determined by immunohistochemistry--appears to be time, tissue and species specific with spleen, heart and retinae being particularly responsive in certain situations. Chapter 4: Protein concentrations of proliferating cell nuclear antigen are tissue specific and variably heat responsive. Surprisingly, levels appear to be positively correlated with C/EBP-delta. Chapter 5: Flow cytometry revealed increasingly high temperatures reduce the proportion of G1 cells while increasing the abundance of apoptotic cells. Chapter 6: These findings are discussed in the context of global climate change and the cellular stress response. Title: CCAAT/Enhancer-Binding Protein Delta (C/EBP-delta) Expression in Antarctic Fishes: Implications for Cell Cycle and Apoptosis Author: Sleadd, Isaac Martin Year: 2013 Chapter 1: Antarctic fishes are extremely cold adapted. Despite their inability to upregulate heat shock proteins, recent studies have demonstrated a capacity for heat response in these animals. A cDNA microarray study looked at the Notothenioid fish Trematomus bernacchii and revealed heat sensitivities for hundreds of genes, two of which code for members of the CCAAT/Enhancer-binding protein (C/EBP) family of transcription factors. These molecular switches are best known for their roles in apoptosis, inflammation and cell cycle arrest. This dissertation further elucidates the role of C/EBP-delta in the Antarctic fishes T. bernacchii and Pagothenia borchgrevinki. Chapter 2: C/EBP-delta is constitutively expressed in unstressed, field-acclimated (ca. -1.86°C) animals in a highly tissue-specific manner. White muscle tissue contains the highest C/EBP-delta concentration, which is further increased in response to sublethal heat stress at 2.0 or 4.0°C. This response is mostly acute and transitory, but a lesser upregulation was observed in fishes held for one month at 4.0°C. Chapter 3: The heat-induced nuclear translocation of C/EBP-delta--as determined by immunohistochemistry--appears to be time, tissue and species specific with spleen, heart and retinae being particularly responsive in certain situations. Chapter 4: Protein concentrations of proliferating cell nuclear antigen are tissue specific and variably heat responsive. Surprisingly, levels appear to be positively correlated with C/EBP-delta. Chapter 5: Flow cytometry revealed increasingly high temperatures reduce the proportion of G1 cells while increasing the abundance of apoptotic cells. Chapter 6: These findings are discussed in the context of global climate change and the cellular stress response. Close

• 3. [Article] Rapid Change in Shallow Water Fish Species Composition in an Historically Stable Antarctic Environment

  McMurdo Sound, Antarctica, is home to a unique marine biota with an ecology that has evolved in this frigid environment over millions of years. The region is one of the least disturbed, and possibly the ...

  Citation × Citation Citation Abstract Copy Title: Rapid Change in Shallow Water Fish Species Composition in an Historically Stable Antarctic Environment Author: Buckley, Bradley A. Year: 2013 McMurdo Sound, Antarctica, is home to a unique marine biota with an ecology that has evolved in this frigid environment over millions of years. The region is one of the least disturbed, and possibly the last pristine, marine ecosystem on Earth. Here, the results of three seasons of fishing in the shallow nearshore waters of McMurdo Sound are reported. A shift in the composition of small fish species at one site, Inaccessible Island, has been observed in just five years. The shift in shallow water species composition occurred during a period that followed the maturation of a commercial fishery for the Antarctic toothfish, Dissostichus mawsoni Norman, a predator of smaller fish, and the presence of a large iceberg, termed B-15, at the mouth of McMurdo Sound during the early 2000s that trapped the annual sea ice in the area leading to the unusual accrual of multi-year sea ice. The data presented here provide a current record of species composition and physiological condition of small, shallow water fishes at three sites in McMurdo Sound, providing a current baseline for the assessment of future changes wrought by environmental changes and unprecedented fishery pressures in the Ross Sea. Title: Rapid Change in Shallow Water Fish Species Composition in an Historically Stable Antarctic Environment Author: Buckley, Bradley A. Year: 2013 McMurdo Sound, Antarctica, is home to a unique marine biota with an ecology that has evolved in this frigid environment over millions of years. The region is one of the least disturbed, and possibly the last pristine, marine ecosystem on Earth. Here, the results of three seasons of fishing in the shallow nearshore waters of McMurdo Sound are reported. A shift in the composition of small fish species at one site, Inaccessible Island, has been observed in just five years. The shift in shallow water species composition occurred during a period that followed the maturation of a commercial fishery for the Antarctic toothfish, Dissostichus mawsoni Norman, a predator of smaller fish, and the presence of a large iceberg, termed B-15, at the mouth of McMurdo Sound during the early 2000s that trapped the annual sea ice in the area leading to the unusual accrual of multi-year sea ice. The data presented here provide a current record of species composition and physiological condition of small, shallow water fishes at three sites in McMurdo Sound, providing a current baseline for the assessment of future changes wrought by environmental changes and unprecedented fishery pressures in the Ross Sea. Close

• 4. [Article] Modeling Fishery Regulation and Compliance: A Case Study of the Yellowtail Rockfish

  Motivated by declining fish populations and the apparent inability of regulatory agencies to manage important fisheries, this research measures the accuracy of a fishery model that explicitly models the ...

  Citation × Citation Citation Abstract Copy Title: Modeling Fishery Regulation and Compliance: A Case Study of the Yellowtail Rockfish Author: Wakeland, Wayne Year: 2007 Motivated by declining fish populations and the apparent inability of regulatory agencies to manage important fisheries, this research measures the accuracy of a fishery model that explicitly models the regulatory process and the resulting degree of compliance by fishers. The method involved careful review and enhancement of a prior model with more limited regulatory sub model, and then measuring, for both models, the mean absolute error of model calculated values for historical spawning biomass, acceptable biological catch, and harvest. The most recent five years of data were held back so that model prediction error could also be computed. Results indicated that although the fitness error for the enhanced model was significantly less than the prior model (23% vs. 38%), predictions were improved only for one of the three measures. The implications for researchers seeking to endogenously model fishery management processes are sobering. Policy makers on the other hand will likely see the results as support for their instinctual skepticism regarding policy models. Title: Modeling Fishery Regulation and Compliance: A Case Study of the Yellowtail Rockfish Author: Wakeland, Wayne Year: 2007 Motivated by declining fish populations and the apparent inability of regulatory agencies to manage important fisheries, this research measures the accuracy of a fishery model that explicitly models the regulatory process and the resulting degree of compliance by fishers. The method involved careful review and enhancement of a prior model with more limited regulatory sub model, and then measuring, for both models, the mean absolute error of model calculated values for historical spawning biomass, acceptable biological catch, and harvest. The most recent five years of data were held back so that model prediction error could also be computed. Results indicated that although the fitness error for the enhanced model was significantly less than the prior model (23% vs. 38%), predictions were improved only for one of the three measures. The implications for researchers seeking to endogenously model fishery management processes are sobering. Policy makers on the other hand will likely see the results as support for their instinctual skepticism regarding policy models. Close

• 5. [Article] Pharmaceutical Contaminants as Stressors on Rocky Intertidal and Estuarine Organisms: a Case Study of Fluoxetine

  Contaminants such as pharmaceuticals are of increasing concern due to their ubiquitous use and persistence in surface waters worldwide. Limited attention has been paid to the effects of pharmaceuticals ...

  Citation × Citation Citation Abstract Copy Title: Pharmaceutical Contaminants as Stressors on Rocky Intertidal and Estuarine Organisms: a Case Study of Fluoxetine Author: Peters, Joseph Richard Year: 2016 Contaminants such as pharmaceuticals are of increasing concern due to their ubiquitous use and persistence in surface waters worldwide. Limited attention has been paid to the effects of pharmaceuticals on marine life, despite widespread detection of these contaminants in the marine environment. Of the existing studies, the majority assess the negative effects of pharmaceuticals over an exposure period of 30 days or less and focus on cellular and subcellular biomarkers. Longer studies are required to determine if chronic contaminant exposure poses risks to marine life at environmentally relevant concentrations. Also scarce in the literature is examination of whole organism effects to identify potential community-level consequences. Two long-term studies with the antidepressant pharmaceutical, fluoxetine (the active constituent in Prozac®) were conducted to determine whether nominal concentrations detected in estuarine and coastal environments affect organism health and interactions. First, we measured whole organism metrics in the California mussel, Mytilus californianus over a period of 107 days. Specifically, we measured algal clearance rates, growth, and condition indices for both reproductive and overall health. We found that fluoxetine negatively affects all measured characteristics, however many effects are mediated by length of exposure. Perhaps the most notable result was that mussels spiked with fluoxetine cleared less algae after 30 days of exposure. Reduced growth and condition indices likely are a consequence of improper nutrition among fluoxetine-treated mussels. Any level of fluoxetine significantly affected the gonadosomatic index after 47 days. The results from this study on mussels fill an important data gap, highlighting organism-level effects of chronic exposure periods; such data more explicitly identify the impacts of pharmaceuticals and other contaminants on marine communities and ecosystems. Fluoxetine has also been documented to affect the behavior of fish and invertebrates, including freshwater and marine bivalves, crustaceans, and fish. Given that other crustaceans exhibited increased activity levels under fluoxetine exposure, we hypothesized that this would subject them to greater predation risk. In our second exposure study, we assessed whether a similar range of fluoxetine concentrations used in the mussel study altered the risk behavior of the Oregon mud crab, Hemigrapsus oregonensis, in response to a common predator, the red rock crab, Cancer productus. We conducted this study for 60 days, conducting day and night behavioral trials (with and without predators) four times a week. We found that crabs exposed to any amount of fluoxetine (3 or 30 ng/L) had increased activity levels relative to controls; however behaviors of 3 ng/L-spiked crabs were not always significantly different from controls. Among control crabs, day and night trials yielded similar results, where a clear response to the addition of the predator was observed. Crabs dosed with fluoxetine exhibited more foraging and active behaviors in the presence of the predator. Additionally, crabs spiked with fluoxetine at 30 ng/L had the greatest risk of mortality either by predation by red rock crabs or due to more aggressive behaviors among conspecifics. The results of this study shed light on a particularly unexplored area of contaminants research: how do psychoactive pharmaceuticals affect animal behavior when exposed to the low concentrations persisting in the aquatic environment for a prolonged period of time? Title: Pharmaceutical Contaminants as Stressors on Rocky Intertidal and Estuarine Organisms: a Case Study of Fluoxetine Author: Peters, Joseph Richard Year: 2016 Contaminants such as pharmaceuticals are of increasing concern due to their ubiquitous use and persistence in surface waters worldwide. Limited attention has been paid to the effects of pharmaceuticals on marine life, despite widespread detection of these contaminants in the marine environment. Of the existing studies, the majority assess the negative effects of pharmaceuticals over an exposure period of 30 days or less and focus on cellular and subcellular biomarkers. Longer studies are required to determine if chronic contaminant exposure poses risks to marine life at environmentally relevant concentrations. Also scarce in the literature is examination of whole organism effects to identify potential community-level consequences. Two long-term studies with the antidepressant pharmaceutical, fluoxetine (the active constituent in Prozac®) were conducted to determine whether nominal concentrations detected in estuarine and coastal environments affect organism health and interactions. First, we measured whole organism metrics in the California mussel, Mytilus californianus over a period of 107 days. Specifically, we measured algal clearance rates, growth, and condition indices for both reproductive and overall health. We found that fluoxetine negatively affects all measured characteristics, however many effects are mediated by length of exposure. Perhaps the most notable result was that mussels spiked with fluoxetine cleared less algae after 30 days of exposure. Reduced growth and condition indices likely are a consequence of improper nutrition among fluoxetine-treated mussels. Any level of fluoxetine significantly affected the gonadosomatic index after 47 days. The results from this study on mussels fill an important data gap, highlighting organism-level effects of chronic exposure periods; such data more explicitly identify the impacts of pharmaceuticals and other contaminants on marine communities and ecosystems. Fluoxetine has also been documented to affect the behavior of fish and invertebrates, including freshwater and marine bivalves, crustaceans, and fish. Given that other crustaceans exhibited increased activity levels under fluoxetine exposure, we hypothesized that this would subject them to greater predation risk. In our second exposure study, we assessed whether a similar range of fluoxetine concentrations used in the mussel study altered the risk behavior of the Oregon mud crab, Hemigrapsus oregonensis, in response to a common predator, the red rock crab, Cancer productus. We conducted this study for 60 days, conducting day and night behavioral trials (with and without predators) four times a week. We found that crabs exposed to any amount of fluoxetine (3 or 30 ng/L) had increased activity levels relative to controls; however behaviors of 3 ng/L-spiked crabs were not always significantly different from controls. Among control crabs, day and night trials yielded similar results, where a clear response to the addition of the predator was observed. Crabs dosed with fluoxetine exhibited more foraging and active behaviors in the presence of the predator. Additionally, crabs spiked with fluoxetine at 30 ng/L had the greatest risk of mortality either by predation by red rock crabs or due to more aggressive behaviors among conspecifics. The results of this study shed light on a particularly unexplored area of contaminants research: how do psychoactive pharmaceuticals affect animal behavior when exposed to the low concentrations persisting in the aquatic environment for a prolonged period of time? Close

• 6. [Article] Hearing loss in stranded odontocete dolphins and whales

  The causes of dolphin and whale stranding can often be difficult to determine. Because toothed whales rely on echolocation for orientation and feeding, hearing deficits could lead to stranding. We report ...

  Citation × Citation Citation Abstract Copy Title: Hearing loss in stranded odontocete dolphins and whales Author: Mann, David, Hill-Cook, Mandy, Manire, Charles, Greenhow, Danielle, Montie, Eric, Powell, Jessica, Wells, Randall, Bauer, Gordon, Cunningham-Smith, Petra, Lingenfelser, Robert, DiGiovanni, Robert, Stone, Abigale, Brodsky, Micah, Stevens, Robert, Kieffer, George, Hoetjes, Paul Year: 2010 The causes of dolphin and whale stranding can often be difficult to determine. Because toothed whales rely on echolocation for orientation and feeding, hearing deficits could lead to stranding. We report on the results of auditory evoked potential measurements from eight species of odontocete cetaceans that were found stranded or severely entangled in fishing gear during the period 2004 through 2009. Approximately 57% of the bottlenose dolphins and 36% of the rough-toothed dolphins had significant hearing deficits with a reduction in sensitivity equivalent to severe (70-90 dB) or profound (>90 dB) hearing loss in humans. The only stranded short-finned pilot whale examined had profound hearing loss. No impairments were detected in seven Risso's dolphins from three different stranding events, two pygmy killer whales, one Atlantic spotted dolphin, one spinner dolphin, or a juvenile Gervais' beaked whale. Hearing impairment could play a significant role in some cetacean stranding events, and the hearing of all cetaceans in rehabilitation should be tested. Title: Hearing loss in stranded odontocete dolphins and whales Author: Mann, David, Hill-Cook, Mandy, Manire, Charles, Greenhow, Danielle, Montie, Eric, Powell, Jessica, Wells, Randall, Bauer, Gordon, Cunningham-Smith, Petra, Lingenfelser, Robert, DiGiovanni, Robert, Stone, Abigale, Brodsky, Micah, Stevens, Robert, Kieffer, George, Hoetjes, Paul Year: 2010 The causes of dolphin and whale stranding can often be difficult to determine. Because toothed whales rely on echolocation for orientation and feeding, hearing deficits could lead to stranding. We report on the results of auditory evoked potential measurements from eight species of odontocete cetaceans that were found stranded or severely entangled in fishing gear during the period 2004 through 2009. Approximately 57% of the bottlenose dolphins and 36% of the rough-toothed dolphins had significant hearing deficits with a reduction in sensitivity equivalent to severe (70-90 dB) or profound (>90 dB) hearing loss in humans. The only stranded short-finned pilot whale examined had profound hearing loss. No impairments were detected in seven Risso's dolphins from three different stranding events, two pygmy killer whales, one Atlantic spotted dolphin, one spinner dolphin, or a juvenile Gervais' beaked whale. Hearing impairment could play a significant role in some cetacean stranding events, and the hearing of all cetaceans in rehabilitation should be tested. Close

• 7. [Article] Insulin-like Growth Factor Pathway Described in <i>Austrofundulus limnaeus</i> Diapause and Escape Embryos

  Development in the annual killifish Austrofundulus limnaeus can follow two distinct developmental trajectories. Typical development includes the entrance of embryos into a state of metabolic and developmental ...

  Citation × Citation Citation Abstract Copy Title: Insulin-like Growth Factor Pathway Described in <i>Austrofundulus limnaeus</i> Diapause and Escape Embryos Author: Woll, Steven Cody Year: 2016 Development in the annual killifish Austrofundulus limnaeus can follow two distinct developmental trajectories. Typical development includes the entrance of embryos into a state of metabolic and developmental arrest termed diapause. Alternately, embryos can escape diapause and develop directly without pause. These two trajectories are characterized by differences in the rate and timing of developmental, morphological, and physiological traits. Insulin and Insulin-like growth factor (IGF) signaling (IIS) is known to regulate entrance into diapause in a variety of invertebrates. In this thesis I explore the possible role of IGFs in the regulation of development and diapause in embryos of A. limnaeus. Here I report stage-specific expression of IGF-I and II proteins and their associated mRNA transcripts. Patterns of IGF-I protein expression are consistent with IGF signaling playing a major role in supporting the escape trajectory. In addition, treatment of embryos with a potent inhibitor of the IGF-I receptor (IGF1R) mimics the diapause developmental pattern even under conditions that should favor direct development. Evaluation of mRNA gene expression patterns in the two developmental trajectories suggests a role for IGF-I signaling through the RAS-MAPK-ERK pathway, which may be promoting the escape phenotype. Additionally, IGF-I activity may be enhanced in escape trajectory embryos though upregulation of IGF binding protein 2 (IGFBP-2) mRNA. These data suggest a major role for IGF signaling in the promotion of the escape trajectory, and thus we predict that specific mechanisms are in place in diapause-bound embryos that block IGF signaling and thus promote entrance into diapause. The data presented here suggest that blocking IGF signaling is critical for induction of diapause, but also suggests that other signaling pathways are likely also at play. Other pathways such at the TGF-beta signaling molecules and SMAD pathway, may also be involved in the direct regulation of the diapause phenotype, as has been shown for other animal models of developmental arrest. Title: Insulin-like Growth Factor Pathway Described in <i>Austrofundulus limnaeus</i> Diapause and Escape Embryos Author: Woll, Steven Cody Year: 2016 Development in the annual killifish Austrofundulus limnaeus can follow two distinct developmental trajectories. Typical development includes the entrance of embryos into a state of metabolic and developmental arrest termed diapause. Alternately, embryos can escape diapause and develop directly without pause. These two trajectories are characterized by differences in the rate and timing of developmental, morphological, and physiological traits. Insulin and Insulin-like growth factor (IGF) signaling (IIS) is known to regulate entrance into diapause in a variety of invertebrates. In this thesis I explore the possible role of IGFs in the regulation of development and diapause in embryos of A. limnaeus. Here I report stage-specific expression of IGF-I and II proteins and their associated mRNA transcripts. Patterns of IGF-I protein expression are consistent with IGF signaling playing a major role in supporting the escape trajectory. In addition, treatment of embryos with a potent inhibitor of the IGF-I receptor (IGF1R) mimics the diapause developmental pattern even under conditions that should favor direct development. Evaluation of mRNA gene expression patterns in the two developmental trajectories suggests a role for IGF-I signaling through the RAS-MAPK-ERK pathway, which may be promoting the escape phenotype. Additionally, IGF-I activity may be enhanced in escape trajectory embryos though upregulation of IGF binding protein 2 (IGFBP-2) mRNA. These data suggest a major role for IGF signaling in the promotion of the escape trajectory, and thus we predict that specific mechanisms are in place in diapause-bound embryos that block IGF signaling and thus promote entrance into diapause. The data presented here suggest that blocking IGF signaling is critical for induction of diapause, but also suggests that other signaling pathways are likely also at play. Other pathways such at the TGF-beta signaling molecules and SMAD pathway, may also be involved in the direct regulation of the diapause phenotype, as has been shown for other animal models of developmental arrest. Close

• 8. [Article] A multi-gene phylogeny of Cephalopoda supports convergent morphological evolution in association with multiple habitat shifts in the marine environment

  The marine environment is comprised of numerous divergent organisms living under similar selective pressures, often resulting in the evolution of convergent structures such as the fusiform body shape of ...

  Citation × Citation Citation Abstract Copy Title: A multi-gene phylogeny of Cephalopoda supports convergent morphological evolution in association with multiple habitat shifts in the marine environment Author: Lindgren, Annie R., Pankey, Molly S., Hochberg, Frederick G., Oakley, Todd H. Year: 2012 The marine environment is comprised of numerous divergent organisms living under similar selective pressures, often resulting in the evolution of convergent structures such as the fusiform body shape of pelagic squids, fishes, and some marine mammals. However, little is known about the frequency of, and circumstances leading to, convergent evolution in the open ocean. Here, we present a comparative study of the molluscan class Cephalopoda, a marine group known to occupy habitats from the intertidal to the deep sea. Several lineages bear features that may coincide with a benthic or pelagic existence, making this a valuable group for testing hypotheses of correlated evolution. To test for convergence and correlation, we generate the most taxonomically comprehensive multi-gene phylogeny of cephalopods to date. We then create a character matrix of habitat type and morphological characters, which we use to infer ancestral character states and test for correlation between habitat and morphology. Our study utilizes a taxonomically well-sampled phylogeny to show convergent evolution in all six morphological characters we analyzed. Three of these characters also correlate with habitat. The presence of an autogenic photophore (those relying upon autonomous enzymatic light reactions) is correlated with a pelagic habitat, while the cornea and accessory nidamental gland correlate with a benthic lifestyle. Here, we present the first statistical tests for correlation between convergent traits and habitat in cephalopods to better understand the evolutionary history of characters that are adaptive in benthic or pelagic environments, respectively. Our study supports the hypothesis that habitat has influenced convergent evolution in the marine environment: benthic organisms tend to exhibit similar characteristics that confer protection from invasion by other benthic taxa, while pelagic organisms possess features that facilitate crypsis and communication in an environment lacking physical refuges. Features that have originated multiple times in distantly related lineages are likely adaptive for the organisms inhabiting a particular environment: studying the frequency and evolutionary history of such convergent characters can increase understanding of the underlying forces driving ecological and evolutionary transitions in the marine environment. Title: A multi-gene phylogeny of Cephalopoda supports convergent morphological evolution in association with multiple habitat shifts in the marine environment Author: Lindgren, Annie R., Pankey, Molly S., Hochberg, Frederick G., Oakley, Todd H. Year: 2012 The marine environment is comprised of numerous divergent organisms living under similar selective pressures, often resulting in the evolution of convergent structures such as the fusiform body shape of pelagic squids, fishes, and some marine mammals. However, little is known about the frequency of, and circumstances leading to, convergent evolution in the open ocean. Here, we present a comparative study of the molluscan class Cephalopoda, a marine group known to occupy habitats from the intertidal to the deep sea. Several lineages bear features that may coincide with a benthic or pelagic existence, making this a valuable group for testing hypotheses of correlated evolution. To test for convergence and correlation, we generate the most taxonomically comprehensive multi-gene phylogeny of cephalopods to date. We then create a character matrix of habitat type and morphological characters, which we use to infer ancestral character states and test for correlation between habitat and morphology. Our study utilizes a taxonomically well-sampled phylogeny to show convergent evolution in all six morphological characters we analyzed. Three of these characters also correlate with habitat. The presence of an autogenic photophore (those relying upon autonomous enzymatic light reactions) is correlated with a pelagic habitat, while the cornea and accessory nidamental gland correlate with a benthic lifestyle. Here, we present the first statistical tests for correlation between convergent traits and habitat in cephalopods to better understand the evolutionary history of characters that are adaptive in benthic or pelagic environments, respectively. Our study supports the hypothesis that habitat has influenced convergent evolution in the marine environment: benthic organisms tend to exhibit similar characteristics that confer protection from invasion by other benthic taxa, while pelagic organisms possess features that facilitate crypsis and communication in an environment lacking physical refuges. Features that have originated multiple times in distantly related lineages are likely adaptive for the organisms inhabiting a particular environment: studying the frequency and evolutionary history of such convergent characters can increase understanding of the underlying forces driving ecological and evolutionary transitions in the marine environment. Close