1
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Griffis‐Kyle KL, LeVering K, Vega A, Perez‐Martinez CA, Barun A, Perry G. Reproductive niche differentiation in syntopic tropical tree frogs (
Agalychnis
). Biotropica 2022. [DOI: 10.1111/btp.13162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
| | | | | | - Christian A. Perez‐Martinez
- Museum of Comparative Zoology Harvard University Cambridge Massachusetts USA
- Division of Biological Sciences University of Missouri Columbia Missouri USA
| | - Arijana Barun
- Metropolitan State University of Denver Denver Colorado USA
| | - Gad Perry
- Texas Tech University Lubbock Texas USA
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2
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Jung J, Guo M, Crovella ME, McDaniel JG, Warkentin KM. Frog embryos use multiple levels of temporal pattern in risk assessment for vibration-cued escape hatching. Anim Cogn 2022; 25:1527-1544. [PMID: 35668245 DOI: 10.1007/s10071-022-01634-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 05/02/2022] [Accepted: 05/06/2022] [Indexed: 12/01/2022]
Abstract
Stereotyped signals can be a fast, effective means of communicating danger, but animals assessing predation risk must often use more variable incidental cues. Red eyed-treefrog, Agalychnis callidryas, embryos hatch prematurely to escape from egg predators, cued by vibrations in attacks, but benign rain generates vibrations with overlapping properties. Facing high false-alarm costs, embryos use multiple vibration properties to inform hatching, including temporal pattern elements such as pulse durations and inter-pulse intervals. However, measures of snake and rain vibration as simple pulse-interval patterns are a poor match to embryo behavior. We used vibration playbacks to assess if embryos use a second level of temporal pattern, long gaps within a rhythmic pattern, as indicators of risks. Long vibration-free periods are common during snake attacks but absent from hard rain. Long gaps after a few initial vibrations increase the hatching response to a subsequent vibration series. Moreover, vibration patterns as short as three pulses, separated by long periods of silence, can induce as much hatching as rhythmic pulse series with five times more vibration. Embryos can retain information that increases hatching over at least 45 s of silence. This work highlights that embryo behavior is contextually modulated in complex ways. Identical vibration pulses, pulse groups, and periods of silence can be treated as risk cues in some contexts and not in others. Embryos employ a multi-faceted decision-making process to effectively distinguish between risk cues and benign stimuli.
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Affiliation(s)
- Julie Jung
- Department of Biology, Boston University, 5 Cummington Mall, Boston, MA, 02215, USA.
| | - Ming Guo
- Department of Biology, Boston University, 5 Cummington Mall, Boston, MA, 02215, USA
| | - Mark E Crovella
- Department of Computer Science, 111 Cummington Mall, Boston, MA, 02215, USA
| | - J Gregory McDaniel
- Department of Mechanical Engineering, 110 Cummington Mall, Boston, MA, 02215, USA
| | - Karen M Warkentin
- Department of Biology, Boston University, 5 Cummington Mall, Boston, MA, 02215, USA.,Smithsonian Tropical Research Institute, Apartado Postal 0843-03092, Panama, Republic of Panama
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3
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Urbina J, Bredeweg EM, Blaustein AR, Garcia TS. Direct and Latent Effects of Pathogen Exposure Across Native and Invasive Amphibian Life Stages. Front Vet Sci 2021; 8:732993. [PMID: 34778428 PMCID: PMC8585985 DOI: 10.3389/fvets.2021.732993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 09/28/2021] [Indexed: 11/13/2022] Open
Abstract
Emerging infectious diseases are one of the multiple factors contributing to the current "biodiversity crisis". As part of the worldwide biodiversity crisis, amphibian populations are declining globally. Chytridiomycosis, an emerging infectious disease, caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd), is a major cause of amphibian population declines. This fungus primarily affects keratinized structures in larval, juvenile, and adult amphibians as well as heart function. However, we know little about how Bd can impact embryos as well as potential latent effects of Bd exposure over ontogeny. Using two different Bd strains and multiple exposure times, we examined the effects of Bd exposure in Pacific chorus frog (Pseudacris regilla), Western toad (Anaxyrus boreas) and American bullfrog (Lithobates catesbeianus) life stages. Using a factorial experimental design, embryos of these three species were exposed to Bd at early and late embryonic stages, with some individuals re-exposed after hatching. Embryonic Bd exposure resulted in differential survival as a function of host species, Bd strain and timing of exposure. P. regilla experienced embryonic mortality when exposed during later developmental stages to one Bd strain. There were no differences across the treatments in embryonic mortality of A. boreas and embryonic mortality of L. catesbeianus occurred in all Bd exposure treatments. We detected latent effects in A. boreas and L. catesbeianus larvae, as mortality increased when individuals had been exposed to any of the Bd strains during the embryonic stage. We also detected direct effects on larval mortality in all three anuran species as a function of Bd strain, and when individuals were double exposed (late in the embryonic stage and again as larvae). Our results suggest that exposure to Bd can directly affect embryo survival and has direct and latent effects on larvae survival of both native and invasive species. However, these impacts were highly context dependent, with timing of exposure and Bd strain influencing the severity of the effects.
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Affiliation(s)
- Jenny Urbina
- Environmental Sciences Graduate Program, Oregon State University, Corvallis, OR, United States
| | - Evan M Bredeweg
- Department of Fisheries, Wildlife and Conservation Sciences, Oregon State University, Corvallis, OR, United States
| | - Andrew R Blaustein
- Department of Integrative Biology, Oregon State University, Corvallis, OR, United States
| | - Tiffany S Garcia
- Department of Fisheries, Wildlife and Conservation Sciences, Oregon State University, Corvallis, OR, United States
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4
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Escape-hatching decisions show adaptive ontogenetic changes in how embryos manage ambiguity in predation risk cues. Behav Ecol Sociobiol 2021. [DOI: 10.1007/s00265-021-03070-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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5
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Erhunmwunse NO, Tongo I, Ezemonye LI. Acute effects of acetaminophen on the developmental, swimming performance and cardiovascular activities of the African catfish embryos/larvae (Clarias gariepinus). ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 208:111482. [PMID: 33120276 DOI: 10.1016/j.ecoenv.2020.111482] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Revised: 10/07/2020] [Accepted: 10/09/2020] [Indexed: 06/11/2023]
Abstract
Acetaminophen is a widely used analgesic that has been detected in many water bodies with few reports concerning its potential toxicity to fish. This study sought to assess the developmental, swimming performance and cardiovascular activities of embryo/larvae catfish (Clarias gariepinus) exposed to acetaminophen. The Organization for Economic Development (OECD) Fish Embryo Acute Toxicity Test (OECD 236) was employed. Fertilized embryo were exposed to different concentrations of acetaminophen (0, 0.5, 1, 10 µg/L) for 96 h. Hatching rates of the embryo were observed to decrease with increasing concentrations of acetaminophen. Fish embryo exposed to acetaminophen displayed varying levels of teratogenic effects at different levels of development in a dose-dependent manner. The results also showed a significant (p < 0.05) dose-dependent increase in swimming speed and movement patterns in fish larvae exposed to acetaminophen, with distance travelled in larvae exposed to the highest concentration of acetaminophen (10 µg/L) about eight (8) times the distance travelled by the control larvae, indicating that acetaminophen-induced erratic swimming behaviour in the catfish species. Cardiotoxicity was evident, with a significant reduction in heartbeat rate with increasing concentrations of acetaminophen. The results showed that exposure to acetaminophen resulted in teratogenic, neurotoxic and cardiotoxic effects in embryo/larvae of Clarias gariepinus. The findings suggest that acetaminophen which has recently been detected in many water bodies could potentially impact on survival of aquatic life, especially catfish.
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Affiliation(s)
| | - Isioma Tongo
- Laboratory for Ecotoxicology and Environmental Forensics, University of Benin, PMB 1154, Benin City, Nigeria; Igbinedion University Okada, Benin City, Edo State, Nigeria
| | - Lawrence Ikechukwu Ezemonye
- Laboratory for Ecotoxicology and Environmental Forensics, University of Benin, PMB 1154, Benin City, Nigeria; Igbinedion University Okada, Benin City, Edo State, Nigeria
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6
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Sánchez-Ochoa DJ, Pérez-Mendoza HA, Charruau P. Oviposition Site Selection and Conservation Insights of Two Tree Frogs (Agalychnis moreletii and A. callidryas
). SOUTH AMERICAN JOURNAL OF HERPETOLOGY 2020. [DOI: 10.2994/sajh-d-17-00103.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- Daniel Joaquín Sánchez-Ochoa
- Laboratorio de Ecología Evolutiva y Conservación de Anfibios y Reptiles, Facultad de Estudios Superiores Iztacala, Universidad Autónoma de México, Av. De Los Barrios 1, Los Reyes Iztacala, 54090 Tlalnepantla, Mexico
| | - Hibraim Adán Pérez-Mendoza
- Laboratorio de Ecología Evolutiva y Conservación de Anfibios y Reptiles, Facultad de Estudios Superiores Iztacala, Universidad Autónoma de México, Av. De Los Barrios 1, Los Reyes Iztacala, 54090 Tlalnepantla, Mexico
| | - Pierre Charruau
- Departamento de Investigación, Centro de Cambio Global y la Sustentabilidad en el Sureste, Calle Centenario del Instituto Juárez, Col. Reforma, C.P. 86080 Villahermosa, Tabasco, Mexico
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7
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Atherton JA, McCormick MI. Parents know best: transgenerational predator recognition through parental effects. PeerJ 2020; 8:e9340. [PMID: 32596050 PMCID: PMC7306219 DOI: 10.7717/peerj.9340] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Accepted: 05/20/2020] [Indexed: 11/30/2022] Open
Abstract
In highly biodiverse systems, such as coral reefs, prey species are faced with predatory threats from numerous species. Recognition of predators can be innate, or learned, and can help increase the chance of survival. Research suggests that parental exposure to increased predatory threats can affect the development, behaviour, and ultimately, success of their offspring. Breeding pairs of damselfish (Acanthochromis polyacanthus) were subjected to one of three olfactory and visual treatments (predator, herbivore, or control), and their developing embryos were subsequently exposed to five different chemosensory cues. Offspring of parents assigned to the predator treatment exhibited a mean increase in heart rate two times greater than that of offspring from parents in herbivore or control treatments. This increased reaction to a parentally known predator odour suggests that predator-treated parents passed down relevant threat information to their offspring, via parental effects. This is the first time transgenerational recognition of a specific predator has been confirmed in any species. This phenomenon could influence predator-induced mortality rates and enable populations to adaptively respond to fluctuations in predator composition and environmental changes.
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Affiliation(s)
- Jennifer A Atherton
- College of Science & Engineering, James Cook University of North Queensland, Townsville, Queensland, Australia.,ARC Centre of Excellence for Coral Reef Studies, Townsville, Queensland, Australia
| | - Mark I McCormick
- College of Science & Engineering, James Cook University of North Queensland, Townsville, Queensland, Australia.,ARC Centre of Excellence for Coral Reef Studies, Townsville, Queensland, Australia
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8
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Jung J, Kim SJ, Pérez Arias SM, McDaniel JG, Warkentin KM. How do red-eyed treefrog embryos sense motion in predator attacks? Assessing the role of vestibular mechanoreception. ACTA ACUST UNITED AC 2019; 222:jeb.206052. [PMID: 31586019 DOI: 10.1242/jeb.206052] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 09/28/2019] [Indexed: 01/18/2023]
Abstract
The widespread ability to alter timing of hatching in response to environmental cues can serve as a defense against threats to eggs. Arboreal embryos of red-eyed treefrogs, Agalychnis callidryas, can hatch up to 30% prematurely to escape predation. This escape-hatching response is cued by physical disturbance of eggs during attacks, including vibrations or motion, and thus depends critically on mechanosensory ability. Predator-induced hatching appears later in development than flooding-induced, hypoxia-cued hatching; thus, its onset is not constrained by the development of hatching ability. It may, instead, reflect the development of mechanosensor function. We hypothesize that vestibular mechanoreception mediates escape-hatching in snake attacks, and that the developmental period when hatching-competent embryos fail to flee from snakes reflects a sensory constraint. We assessed the ontogenetic congruence of escape-hatching responses and an indicator of vestibular function, the vestibulo-ocular reflex (VOR), in three ways. First, we measured VOR in two developmental series of embryos 3-7 days old to compare with the published ontogeny of escape success in attacks. Second, during the period of greatest variation in VOR and escape success, we compared hatching responses and VOR across sibships. Finally, in developmental series, we compared the response of individual embryos to a simulated attack cue with their VOR. The onset of VOR and hatching responses were largely concurrent at all three scales. Moreover, latency to hatch in simulated attacks decreased with increasing VOR. These results are consistent with a key role of the vestibular system in the escape-hatching response of A. callidryas embryos to attacks.
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Affiliation(s)
- Julie Jung
- Department of Biology, Boston University, 5 Cummington Mall, Boston, MA, 02215, USA
| | - Su J Kim
- Department of Biology, Boston University, 5 Cummington Mall, Boston, MA, 02215, USA
| | - Sonia M Pérez Arias
- Department of Biology, Boston University, 5 Cummington Mall, Boston, MA, 02215, USA
| | - James G McDaniel
- Department of Mechanical Engineering, 110 Cummington Mall, Boston, MA, 02215, USA
| | - Karen M Warkentin
- Department of Biology, Boston University, 5 Cummington Mall, Boston, MA, 02215, USA.,Gamboa Laboratory, Smithsonian Tropical Research Institute, Apartado Postal 0843-03092, Panamá, República de Panamá
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9
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Warkentin KM, Jung J, Rueda Solano LA, McDaniel JG. Ontogeny of escape-hatching decisions: vibrational cue use changes as predicted from costs of sampling and false alarms. Behav Ecol Sociobiol 2019. [DOI: 10.1007/s00265-019-2663-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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10
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Cohen KL, Piacentino ML, Warkentin KM. Two types of hatching gland cells facilitate escape-hatching at different developmental stages in red-eyed treefrogs, Agalychnis callidryas (Anura: Phyllomedusidae). Biol J Linn Soc Lond 2019. [DOI: 10.1093/biolinnean/bly214] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
| | | | - Karen M Warkentin
- Department of Biology, Boston University, Boston, MA, USA
- Smithsonian Tropical Research Institute, Panamá, República de Panamá
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11
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Abstract
In many animals, eggs within a clutch emerge more or less at the same time. A new study identifies vibrations of eggs cracking open as the cue that triggers synchronous emergence in an insect.
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12
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Güell BA, Warkentin KM. When and where to hatch? Red-eyed treefrog embryos use light cues in two contexts. PeerJ 2018; 6:e6018. [PMID: 30533307 PMCID: PMC6283037 DOI: 10.7717/peerj.6018] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Accepted: 10/27/2018] [Indexed: 12/11/2022] Open
Abstract
Hatching timing is under strong selection and environmentally cued in many species. Embryos use multiple sensory modalities to inform hatching timing and many have spontaneous hatching patterns adaptively synchronized to natural cycles. Embryos can also adaptively shift their hatching timing in response to environmental cues indicating immediate threats or opportunities. Such cued shifts in hatching are widespread among amphibians; however, we know little about what, if anything, regulates their spontaneous hatching. Moreover, in addition to selection on hatching timing, embryos may experience benefits or suffer costs due to the spatial orientation of hatching. Amphibian eggs generally lack internal constraints on hatching direction but embryos might, nonetheless, use external cues to inform hatching orientation. The terrestrial embryos of red-eyed treefrogs, Agalychnis callidryas, hatch rapidly and prematurely in response to vibrational cues in egg-predator attacks and hypoxia if flooded. Here we examined A. callidryas’ use of light cues in hatching timing and orientation. To assess patterns of spontaneous hatching and the role of light cues in their diel timing, we recorded hatching times for siblings distributed across three light environments: continuous light, continuous dark, and a 12L:12D photoperiod. Under a natural photoperiod, embryos showed a clear diel pattern of synchronous hatching shortly after nightfall. Hatching was desynchronized in both continuous light and continuous darkness. It was also delayed by continuous light, but not accelerated by continuous dark, suggesting the onset of dark serves as a hatching cue. We examined hatching orientation and light as a potential directional cue for flooded embryos. Embryos flooded in their clutches almost always hatched toward open water, whereas individual eggs flooded in glass cups often failed to do so, suggesting the natural context provides a directional cue. To test if flooded embryos orient hatching toward light, we placed individual eggs in tubes with one end illuminated and the other dark, then flooded them and recorded hatching direction. Most embryos hatched toward the light, suggesting they use light as a directional cue. Our results support that A. callidryas embryos use light cues to inform both when and where to hatch. Both the spatial orientation of hatching and the timing of spontaneous hatching may affect fitness and be informed by cues in a broader range of species than is currently appreciated.
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Affiliation(s)
- Brandon A Güell
- University of California, San Diego, CA, United States of America.,Department of Biology, Boston University, Boston, MA, United States of America
| | - Karen M Warkentin
- Department of Biology, Boston University, Boston, MA, United States of America.,Smithsonian Tropical Research Institute, Panama City, Panama
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13
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Tills O, Truebano M, Feldmeyer B, Pfenninger M, Morgenroth H, Schell T, Rundle SD. Transcriptomic responses to predator kairomones in embryos of the aquatic snail Radix balthica. Ecol Evol 2018; 8:11071-11082. [PMID: 30519426 PMCID: PMC6262742 DOI: 10.1002/ece3.4574] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Revised: 09/04/2018] [Accepted: 09/05/2018] [Indexed: 12/24/2022] Open
Abstract
The ability of organisms to respond to predation threat by exhibiting induced defenses is well documented, but studies on the potential mechanistic basis for such responses are scarce. Here, we examine the transcriptomic response to predator kairomones of two functionally distinct developmental stages in embryos of the aquatic snail Radix balthica: E8-the stage at which a range-finding trial indicated that kairomone-induced accelerated growth and development first occurred; and E9-the stage at which embryos switched from ciliary- to crawling-driven locomotion. We tested whether expression profiles were influenced by kairomones and whether this influence varied between stages. We also identified potential candidate genes for investigating mechanisms underpinning induced responses. There were 6,741 differentially expressed transcripts between developmental stages, compared to just five in response to predator kairomones. However, on examination of functional enrichment in the transcripts responding to predator kairomones and adopting a less stringent significance threshold, 206 transcripts were identified relating to muscle function, growth, and development, with this response being greater at the later E9 stage. Furthermore, these transcripts included putative annotations for genes identified as responding to predator kairomones in other taxa, including C1q, lectin, and actin domains. Globally, transcript expression appeared reduced in response to predator kairomones and we hypothesize that this might be a result of metabolic suppression, as has been reported in other taxa in response to predation threat.
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Affiliation(s)
- Oliver Tills
- Marine Biology and Ecology Research CentreUniversity of Plymouth, Drake CircusPlymouthUK
| | - Manuela Truebano
- Marine Biology and Ecology Research CentreUniversity of Plymouth, Drake CircusPlymouthUK
| | - Barbara Feldmeyer
- Molecular Ecology Group, Institute for Ecology, Evolution and DiversityGoethe‐UniversityFrankfurt am MainGermany
| | - Markus Pfenninger
- Molecular Ecology Group, Institute for Ecology, Evolution and DiversityGoethe‐UniversityFrankfurt am MainGermany
- Adaptation and ClimateSenckenberg Biodiversity and Climate Research CentreFrankfurt am MainGermany
| | - Holly Morgenroth
- Marine Biology and Ecology Research CentreUniversity of Plymouth, Drake CircusPlymouthUK
| | - Tilman Schell
- Senckenberg Research Institute and Natural History Museum FrankfurtFrankfurtGermany
- LOWE‐TBG Centre for Translational Biodiversity GenomicsFrankfurtGermany
| | - Simon D. Rundle
- Marine Biology and Ecology Research CentreUniversity of Plymouth, Drake CircusPlymouthUK
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14
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Cohen KL, Piacentino ML, Warkentin KM. The hatching process and mechanisms of adaptive hatching acceleration in hourglass treefrogs, Dendropsophus ebraccatus. Comp Biochem Physiol A Mol Integr Physiol 2017; 217:63-74. [PMID: 29056480 DOI: 10.1016/j.cbpa.2017.10.020] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Revised: 10/16/2017] [Accepted: 10/17/2017] [Indexed: 01/25/2023]
Abstract
Environmentally cued hatching is well documented in anurans, enabling embryos to escape diverse threats. However, knowledge of anuran hatching mechanisms is limited and based largely on aquatic-breeding species without known plasticity in hatching timing. Generally, hatching gland cells produce a hatching enzyme that degrades the vitelline membrane. We investigated hatching and its regulation in terrestrial embryos of hourglass treefrogs, Dendropsophus ebraccatus, which accelerate hatching to escape dehydration. We specifically tested if changes in hatching gland cell development or hatching enzyme gene expression are associated with accelerated hatching. We measured perivitelline chamber size of well-hydrated eggs over development as an indicator of breakdown of the vitelline membrane and found that the size of the perivitelline chamber increased steadily until hatching, suggesting gradual hatching enzyme release and vitelline membrane degradation. Hatching gland cells peaked in abundance and began regression substantially prior to hatching, but we found no developmental differences in the abundance or surface area of hatching gland cells between dry and well-hydrated embryos. Hatching enzyme gene expression also peaked early in development then declined, with no difference between hydration treatments. In D. ebraccatus breakdown of the vitelline membrane appears gradual, mediated by hatching enzyme release starting long before hatching. However, hatching acceleration is not associated with ontogenetic changes in hatching gland cell development or hatching enzyme gene expression. This hatching process contrasts with that of red-eyed treefrogs, Agalychnis callidryas, which appear to release enzyme acutely at hatching, yet both species are capable of hatching to escape acute threats.
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Affiliation(s)
- Kristina L Cohen
- Department of Biology, Boston University, 5 Cummington Mall, Boston, MA, 02215, USA.
| | - Michael L Piacentino
- Department of Biology, Boston University, 5 Cummington Mall, Boston, MA, 02215, USA; Program in Molecular Biology, Cell Biology and Biochemistry, Boston University, 5 Cummington Mall, Boston, MA, 02215, USA
| | - Karen M Warkentin
- Department of Biology, Boston University, 5 Cummington Mall, Boston, MA, 02215, USA; Smithsonian Tropical Research Institute, Apartado Postal 0843-03092, Panamá, República de Panamá
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15
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Salica MJ, Vonesh JR, Warkentin KM. Egg clutch dehydration induces early hatching in red-eyed treefrogs, Agalychnis callidryas. PeerJ 2017; 5:e3549. [PMID: 28717595 PMCID: PMC5511700 DOI: 10.7717/peerj.3549] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Accepted: 06/15/2017] [Indexed: 11/27/2022] Open
Abstract
Terrestrial eggs have evolved repeatedly in tropical anurans exposing embryos to the new threat of dehydration. Red-eyed treefrogs, Agalychnis callidryas, lay eggs on plants over water. Maternally provided water allows shaded eggs in humid sites to develop to hatching without rainfall, but unshaded eggs and those in less humid sites can die from dehydration. Hatching responses of amphibian eggs to dry conditions are known from two lineages with independent origins of terrestrial eggs. Here, we experimentally tested for dehydration-induced early hatching in another lineage (Agalychnis callidryas, Phyllomedusidae), representing a third independent origin of terrestrial eggs. We also investigated how dehydration affected egg and clutch structure, and egg mortality. We collected clutches from a pond in Gamboa, Panama, and randomly allocated them to wet or dry treatments at age 1 day. Embryos hatched earlier from dry clutches than from wet clutches, accelerating hatching by ∼11%. Clutch thickness and egg diameter were affected by dehydration, diverging between treatments over time. Meanwhile, mortality in dry clutches was six-fold higher than in control clutches. With this study, early hatching responses to escape mortality from egg dehydration are now known from three anuran lineages with independent origins of terrestrial eggs, suggesting they may be widespread. Further studies are needed to understand how terrestrial amphibian eggs can respond to, or will be affected by, rapid changes in climate over the next decades.
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Affiliation(s)
- María José Salica
- CONICET, Instituto de Ecorregiones Andinas (INECOA), Universidad Nacional de Jujuy, San Salvador de Jujuy, Argentina
| | - James R. Vonesh
- Department of Biology, Virginia Commonwealth University, Richmond, VA, United States of America
| | - Karen M. Warkentin
- Department of Biology, Boston University, Boston, MA, United States of America
- Smithsonian Tropical Research Institute, Panamá, República de Panamá
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16
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17
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The Adhesive Glands during Embryogenesis in Some Species of Phyllomedusinae (Anura: Hylidae). J HERPETOL 2017. [DOI: 10.1670/15-127] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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18
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Knight K. Red-eyed treefrog embryos hatch in seconds. J Exp Biol 2016. [DOI: 10.1242/jeb.143693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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