David Reznick | University of California, Riverside (original) (raw)
Papers by David Reznick
A key goal in evolutionary biology is to understand the maintenance of trait variation in nature.... more A key goal in evolutionary biology is to understand the maintenance of trait variation in nature. This paper explores the ecology, trait variation, and possible adaptation of Trinidad guppies introduced to novel environments. Here we study two important environmental factors leading to changes in color polymorphisms of wild populations, which enable the guppy to survive and thrive under abrupt environmental change. Guppies were initially taken from one high-predation environment and introduced into two geographically isolated low-predation environments, one of which had its canopy trimmed to increase more light. In low predation environments, the expected lifespan increases dramatically, but so does population density, causing a reduction in food availability. The introduced guppies were photographed and measured bimonthly for twelve months for any changes in coloration from their ancestral measurements. Results show that little changes in coloration have occurred since the introduc...
plan: Kinnison-Palkovacs redo with electric exclosures. Focus on trophic cascades and indirect ef... more plan: Kinnison-Palkovacs redo with electric exclosures. Focus on trophic cascades and indirect effects
Life history theory predicts that high extrinsic mortality rates will cause the evolu-tion of ear... more Life history theory predicts that high extrinsic mortality rates will cause the evolu-tion of earlier maturity and increased reproductive effort. Guppies that co-occur with predators support these predictions because they attain maturity at an earlier age and have higher levels of reproductive effort than their counterparts from localities that lack predators. In the past, we used short term (12 day) mark-recapture studies to show that guppy populations that co-occur with predators do in fact have higher mortality rates than those that do not. Here we extend this result to long term mark-recapture studies with a single recapture interval of over 200 days. We show that the recapture probabilities after these longer intervals are very similar to what one would predict based on the short term studies. Because of the multiplicative nature of mortality rate, the differences in recapture rates in guppies from low as opposed to high predation sites are now much more dramatic, on the order ...
In the 2001 film Zoolander, the lead character, played by Ben Stiller, ditches his old “Blue Stee... more In the 2001 film Zoolander, the lead character, played by Ben Stiller, ditches his old “Blue Steel” look and develops an exciting new ‘Magnum” look that the fashion industry enthusiastically embraces. The evil mastermind, Mr Mugato, played by Will Farrell, exclaims “The man has only one look, for Christ’s sake! … They’re the same face! Doesn’t anybody notice this? I feel like I’m taking crazy pills!” We argue here that eco-evolution is the “Magnum” of biology: it is fashionable, lots of people love it, but it is not new. We also argue that, like the “Blue Steel” look in the 2016 sequel, Zoolander 2, eco-evolution is being seen where it does not belong.
Biological Journal of the Linnean Society
Frontiers in Ecology and Evolution
Sexual conflict is caused by differences between the sexes in how fitness is maximized. These dif... more Sexual conflict is caused by differences between the sexes in how fitness is maximized. These differences are shaped by the discrepancy in the investment in gametes, how mates are chosen and how embryos and young are provided for. Fish in the family Poeciliidae vary from completely provisioning eggs before they are fertilized to providing virtually all resources after fertilization via the functional equivalent of a mammalian placenta. This shift in when females provision their young relative to when an egg is fertilized is predicted to cause a fundamental change in when and how sexual conflict is manifested. If eggs are provisioned before fertilization, there should be strong selection for females to choose with whom they mate. Maternal provisioning after fertilization should promote a shift to post-copulatory mate choice. The evolution of maternal provisioning may in turn have cascading effects on the evolution of diverse features of the biology of these fish because of this shift...
The Bulletin of the Ecological Society of America
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences
Darwin and Mendeleev revolutionized their respective disciplines by organizing diverse facts into... more Darwin and Mendeleev revolutionized their respective disciplines by organizing diverse facts into simple, pictorial representations—a tree and a table. Each representation provides a foundation for a scientific theory for two reasons. First, a successful theory unites diverse phenomena under a single explanatory framework. Second, it does so in a way that defines paths for future inquiry that extends its reach and tests its limits. For Mendeleev, this meant creating a table that accommodated the current understanding of the elements but also contained blanks that predicted the discovery of previously unknown elements. More importantly, the structure of the table helped shape future research to define the structure of matter. For Darwin, envisioning life as a tree meant defining the rules that govern the origin of adaptations, species and shape the constantly shifting diversity of life. At the same time, his theory inspired research into the laws of inheritance and created diverse ne...
![Research paper thumbnail of {"__content__"=>"Tissue-Specific Transcriptome for Reveals Evidence for Genetic Adaptation Related to the Evolution of a Placental Fish.", "i"=>[{"__content__"=>"Poeciliopsis"}, {"__content__"=>"prolifica"}]}](https://attachments.academia-assets.com/74269292/thumbnails/1.jpg)
](G3 (Bethesda, Md.), Jul 2, 2018
The evolution of the placenta is an excellent model to examine the evolutionary processes underly... more The evolution of the placenta is an excellent model to examine the evolutionary processes underlying adaptive complexity due to the recent, independent derivation of placentation in divergent animal lineages. In fishes, the family Poeciliidae offers the opportunity to study placental evolution with respect to variation in degree of post-fertilization maternal provisioning among closely related sister species. In this study, we present a detailed examination of a new reference transcriptome sequence for the live-bearing, matrotrophic fish, , from multiple-tissue RNA-seq data. We describe the genetic components active in liver, brain, late-stage embryo, and the maternal placental/ovarian complex, as well as associated patterns of positive selection in a suite of orthologous genes found in fishes. Results indicate the expression of many signaling transcripts, "non-coding" sequences and repetitive elements in the maternal placental/ovarian complex. Moreover, patterns of positi...
Nature Ecology & Evolution
A key goal in evolutionary biology is to understand the maintenance of trait variation in nature.... more A key goal in evolutionary biology is to understand the maintenance of trait variation in nature. This paper explores the ecology, trait variation, and possible adaptation of Trinidad guppies introduced to novel environments. Here we study two important environmental factors leading to changes in color polymorphisms of wild populations, which enable the guppy to survive and thrive under abrupt environmental change. Guppies were initially taken from one high-predation environment and introduced into two geographically isolated low-predation environments, one of which had its canopy trimmed to increase more light. In low predation environments, the expected lifespan increases dramatically, but so does population density, causing a reduction in food availability. The introduced guppies were photographed and measured bimonthly for twelve months for any changes in coloration from their ancestral measurements. Results show that little changes in coloration have occurred since the introduc...
plan: Kinnison-Palkovacs redo with electric exclosures. Focus on trophic cascades and indirect ef... more plan: Kinnison-Palkovacs redo with electric exclosures. Focus on trophic cascades and indirect effects
Life history theory predicts that high extrinsic mortality rates will cause the evolu-tion of ear... more Life history theory predicts that high extrinsic mortality rates will cause the evolu-tion of earlier maturity and increased reproductive effort. Guppies that co-occur with predators support these predictions because they attain maturity at an earlier age and have higher levels of reproductive effort than their counterparts from localities that lack predators. In the past, we used short term (12 day) mark-recapture studies to show that guppy populations that co-occur with predators do in fact have higher mortality rates than those that do not. Here we extend this result to long term mark-recapture studies with a single recapture interval of over 200 days. We show that the recapture probabilities after these longer intervals are very similar to what one would predict based on the short term studies. Because of the multiplicative nature of mortality rate, the differences in recapture rates in guppies from low as opposed to high predation sites are now much more dramatic, on the order ...
In the 2001 film Zoolander, the lead character, played by Ben Stiller, ditches his old “Blue Stee... more In the 2001 film Zoolander, the lead character, played by Ben Stiller, ditches his old “Blue Steel” look and develops an exciting new ‘Magnum” look that the fashion industry enthusiastically embraces. The evil mastermind, Mr Mugato, played by Will Farrell, exclaims “The man has only one look, for Christ’s sake! … They’re the same face! Doesn’t anybody notice this? I feel like I’m taking crazy pills!” We argue here that eco-evolution is the “Magnum” of biology: it is fashionable, lots of people love it, but it is not new. We also argue that, like the “Blue Steel” look in the 2016 sequel, Zoolander 2, eco-evolution is being seen where it does not belong.
Biological Journal of the Linnean Society
Frontiers in Ecology and Evolution
Sexual conflict is caused by differences between the sexes in how fitness is maximized. These dif... more Sexual conflict is caused by differences between the sexes in how fitness is maximized. These differences are shaped by the discrepancy in the investment in gametes, how mates are chosen and how embryos and young are provided for. Fish in the family Poeciliidae vary from completely provisioning eggs before they are fertilized to providing virtually all resources after fertilization via the functional equivalent of a mammalian placenta. This shift in when females provision their young relative to when an egg is fertilized is predicted to cause a fundamental change in when and how sexual conflict is manifested. If eggs are provisioned before fertilization, there should be strong selection for females to choose with whom they mate. Maternal provisioning after fertilization should promote a shift to post-copulatory mate choice. The evolution of maternal provisioning may in turn have cascading effects on the evolution of diverse features of the biology of these fish because of this shift...
The Bulletin of the Ecological Society of America
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences
Darwin and Mendeleev revolutionized their respective disciplines by organizing diverse facts into... more Darwin and Mendeleev revolutionized their respective disciplines by organizing diverse facts into simple, pictorial representations—a tree and a table. Each representation provides a foundation for a scientific theory for two reasons. First, a successful theory unites diverse phenomena under a single explanatory framework. Second, it does so in a way that defines paths for future inquiry that extends its reach and tests its limits. For Mendeleev, this meant creating a table that accommodated the current understanding of the elements but also contained blanks that predicted the discovery of previously unknown elements. More importantly, the structure of the table helped shape future research to define the structure of matter. For Darwin, envisioning life as a tree meant defining the rules that govern the origin of adaptations, species and shape the constantly shifting diversity of life. At the same time, his theory inspired research into the laws of inheritance and created diverse ne...
G3 (Bethesda, Md.), Jul 2, 2018
The evolution of the placenta is an excellent model to examine the evolutionary processes underly... more The evolution of the placenta is an excellent model to examine the evolutionary processes underlying adaptive complexity due to the recent, independent derivation of placentation in divergent animal lineages. In fishes, the family Poeciliidae offers the opportunity to study placental evolution with respect to variation in degree of post-fertilization maternal provisioning among closely related sister species. In this study, we present a detailed examination of a new reference transcriptome sequence for the live-bearing, matrotrophic fish, , from multiple-tissue RNA-seq data. We describe the genetic components active in liver, brain, late-stage embryo, and the maternal placental/ovarian complex, as well as associated patterns of positive selection in a suite of orthologous genes found in fishes. Results indicate the expression of many signaling transcripts, "non-coding" sequences and repetitive elements in the maternal placental/ovarian complex. Moreover, patterns of positi...
Nature Ecology & Evolution