The Experts below are selected from a list of 321 Experts worldwide ranked by ideXlab platform
Randy Thornhill - One of the best experts on this subject based on the ideXlab platform.
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Male parental care, differential parental investment by females and sexual selection ☆
Animal Behaviour, 1998Co-Authors: Anders Pape Møller, Randy ThornhillAbstract:Males play a variable parental role in reproduction, ranging from no male parental care to extensive male care. Females may acquire either direct or indirect fitness benefits from their mate choice, and direct fitness benefits include male parental care. Theoreticians have traditionally emphasized direct fitness benefits to females in species with extensive male parental care. We review the literature and show extensive variation in the patterns of male care, related to the attractiveness of males to females. At one extreme of this continuum, females invest differentially in parental care, investing more when paired with attractive males. The costs of female parental care and other aspects of parental investment may be balanced by benefits in terms of more attractive sons and/or more viable offspring. At the other extreme, in species with extensive direct fitness benefits, males with preferred sexual phenotypes provide the largest relative share of parental care. A comparative study of birds revealed that the extent of the differential female parental investment was directly related to the frequency of extra-pair paternity. Since extra-pair paternity may arise mainly as a consequence of female choice for indirect fitness benefits, this result supports our prediction that differential parental investment is prevalent in species where females benefit indirectly from their mate choice. The consequences for sexual selection theory of these patterns of male care in relation to male attractiveness are emphasized.
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male parental care differential parental investment by females and sexual selection
Animal Behaviour, 1998Co-Authors: Anders Pape Møller, Randy ThornhillAbstract:Males play a variable parental role in reproduction, ranging from no male parental care to extensive male care. Females may acquire either direct or indirect fitness benefits from their mate choice, and direct fitness benefits include male parental care. Theoreticians have traditionally emphasized direct fitness benefits to females in species with extensive male parental care. We review the literature and show extensive variation in the patterns of male care, related to the attractiveness of males to females. At one extreme of this continuum, females invest differentially in parental care, investing more when paired with attractive males. The costs of female parental care and other aspects of parental investment may be balanced by benefits in terms of more attractive sons and/or more viable offspring. At the other extreme, in species with extensive direct fitness benefits, males with preferred sexual phenotypes provide the largest relative share of parental care. A comparative study of birds revealed that the extent of the differential female parental investment was directly related to the frequency of extra-pair paternity. Since extra-pair paternity may arise mainly as a consequence of female choice for indirect fitness benefits, this result supports our prediction that differential parental investment is prevalent in species where females benefit indirectly from their mate choice. The consequences for sexual selection theory of these patterns of male care in relation to male attractiveness are emphasized.
Anders Pape Møller - One of the best experts on this subject based on the ideXlab platform.
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Male parental care, differential parental investment by females and sexual selection ☆
Animal Behaviour, 1998Co-Authors: Anders Pape Møller, Randy ThornhillAbstract:Males play a variable parental role in reproduction, ranging from no male parental care to extensive male care. Females may acquire either direct or indirect fitness benefits from their mate choice, and direct fitness benefits include male parental care. Theoreticians have traditionally emphasized direct fitness benefits to females in species with extensive male parental care. We review the literature and show extensive variation in the patterns of male care, related to the attractiveness of males to females. At one extreme of this continuum, females invest differentially in parental care, investing more when paired with attractive males. The costs of female parental care and other aspects of parental investment may be balanced by benefits in terms of more attractive sons and/or more viable offspring. At the other extreme, in species with extensive direct fitness benefits, males with preferred sexual phenotypes provide the largest relative share of parental care. A comparative study of birds revealed that the extent of the differential female parental investment was directly related to the frequency of extra-pair paternity. Since extra-pair paternity may arise mainly as a consequence of female choice for indirect fitness benefits, this result supports our prediction that differential parental investment is prevalent in species where females benefit indirectly from their mate choice. The consequences for sexual selection theory of these patterns of male care in relation to male attractiveness are emphasized.
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male parental care differential parental investment by females and sexual selection
Animal Behaviour, 1998Co-Authors: Anders Pape Møller, Randy ThornhillAbstract:Males play a variable parental role in reproduction, ranging from no male parental care to extensive male care. Females may acquire either direct or indirect fitness benefits from their mate choice, and direct fitness benefits include male parental care. Theoreticians have traditionally emphasized direct fitness benefits to females in species with extensive male parental care. We review the literature and show extensive variation in the patterns of male care, related to the attractiveness of males to females. At one extreme of this continuum, females invest differentially in parental care, investing more when paired with attractive males. The costs of female parental care and other aspects of parental investment may be balanced by benefits in terms of more attractive sons and/or more viable offspring. At the other extreme, in species with extensive direct fitness benefits, males with preferred sexual phenotypes provide the largest relative share of parental care. A comparative study of birds revealed that the extent of the differential female parental investment was directly related to the frequency of extra-pair paternity. Since extra-pair paternity may arise mainly as a consequence of female choice for indirect fitness benefits, this result supports our prediction that differential parental investment is prevalent in species where females benefit indirectly from their mate choice. The consequences for sexual selection theory of these patterns of male care in relation to male attractiveness are emphasized.
Clive R. Neal - One of the best experts on this subject based on the ideXlab platform.
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Distinguishing high‐alumina Mare basalts using Clementine UVVIS and Lunar Prospector GRS data: Mare Moscoviense and Mare Nectaris
Journal of Geophysical Research, 2008Co-Authors: Georgiana Y. Kramer, Bradley L. Jolliff, Clive R. NealAbstract:[1] High-alumina (HA) Mare basalts are a unique group of the lunar sample collection. Sample geochemistry indicates that these basalts are derived from sources composed of late-stage cumulates from the Lunar Magma Ocean (LMO). Their aluminous nature suggests their sources contained significant plagioclase, which has implications regarding the efficiency of plagioclase separation from earlier forming, mafic cumulates in the LMO to form the anorthositic lunar crust, and hence the heterogeneity of the lunar mantle. The Apollo and Luna missions sampled HA basalts from four different locations that are separated by 80 equatorial degrees (∼2400 km). Radiometric age dating of these samples demonstrates aluminous basaltic volcanism spanned over 1 billion years, suggesting HA basalts may be more prevalent on the Moon than implied by the sample population. Knowing their global occurrence would ultimately enhance our understanding of lunar evolution. Aluminous Mare basalts occupy a unique location in Th-FeO compositional space that suggests they can be identified using global remote-sensing data of the Moon. We present our approach for distinguishing exposures of HA basalts using Clementine ultraviolet-visible-infrared (UVVIS) and Lunar Prospector Gamma Ray Spectrometer (LP-GRS) data with constraints based on the FeO, TiO2, and Th abundances of Apollo and Luna HA samples. We identified 34 regions of interest (ROIs) where HA basalts could be a prominent component of the lunar surface. By analyzing the rims and proximal ejecta from small impacts (0.4–4 km in diameter) into the Mare surface we characterized compositionally distinct basaltic units that make up the Mare and thus determined which units represent HA basalt lavas. The results were used to generate maps that depict discrete Mare units and classify their general basalt type. Here we focus on two ROIs: Mare Moscoviense and Mare Nectaris. Mare Moscoviense is composed of four basaltic units, two of which are HA candidates. Clementine UVVIS data of Mare Nectaris show evidence of up to three Mare basalt units. One is the remnants of a mid-Ti unit that capped earlier low-Ti flows. The majority of the basin is filled by a compositionally indistinguishable low-Fe, low-Ti basalt. However, spectral profiles suggest there are two units. Regardless, the units both fit the criteria for a HA basalt.
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distinguishing high alumina Mare basalts using clementine uvvis and lunar prospector grs data Mare moscoviense and Mare nectaris
Journal of Geophysical Research, 2008Co-Authors: Georgiana Y. Kramer, Bradley L. Jolliff, Clive R. NealAbstract:[1] High-alumina (HA) Mare basalts are a unique group of the lunar sample collection. Sample geochemistry indicates that these basalts are derived from sources composed of late-stage cumulates from the Lunar Magma Ocean (LMO). Their aluminous nature suggests their sources contained significant plagioclase, which has implications regarding the efficiency of plagioclase separation from earlier forming, mafic cumulates in the LMO to form the anorthositic lunar crust, and hence the heterogeneity of the lunar mantle. The Apollo and Luna missions sampled HA basalts from four different locations that are separated by 80 equatorial degrees (∼2400 km). Radiometric age dating of these samples demonstrates aluminous basaltic volcanism spanned over 1 billion years, suggesting HA basalts may be more prevalent on the Moon than implied by the sample population. Knowing their global occurrence would ultimately enhance our understanding of lunar evolution. Aluminous Mare basalts occupy a unique location in Th-FeO compositional space that suggests they can be identified using global remote-sensing data of the Moon. We present our approach for distinguishing exposures of HA basalts using Clementine ultraviolet-visible-infrared (UVVIS) and Lunar Prospector Gamma Ray Spectrometer (LP-GRS) data with constraints based on the FeO, TiO2, and Th abundances of Apollo and Luna HA samples. We identified 34 regions of interest (ROIs) where HA basalts could be a prominent component of the lunar surface. By analyzing the rims and proximal ejecta from small impacts (0.4–4 km in diameter) into the Mare surface we characterized compositionally distinct basaltic units that make up the Mare and thus determined which units represent HA basalt lavas. The results were used to generate maps that depict discrete Mare units and classify their general basalt type. Here we focus on two ROIs: Mare Moscoviense and Mare Nectaris. Mare Moscoviense is composed of four basaltic units, two of which are HA candidates. Clementine UVVIS data of Mare Nectaris show evidence of up to three Mare basalt units. One is the remnants of a mid-Ti unit that capped earlier low-Ti flows. The majority of the basin is filled by a compositionally indistinguishable low-Fe, low-Ti basalt. However, spectral profiles suggest there are two units. Regardless, the units both fit the criteria for a HA basalt.
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Searching for high alumina Mare basalts using Clementine UVVIS and Lunar Prospector GRS data: Mare Fecunditatis and Mare Imbrium
Icarus, 2008Co-Authors: Georgiana Y. Kramer, Bradley L. Jolliff, Clive R. NealAbstract:Abstract In the context of sample evidence alone, the high-alumina (HA) basalts appear to be an unique, and rare variety of Mare basalt. In addition to their distinct chemistry, radiometric dating reveals these basalts to be among the oldest sampled Mare basalts. Yet, HA basalts were sampled by four missions spanning a lateral range of ∼2400 km, with ages demonstrating that aluminous volcanism lasted at least 1 billion years. This evidence suggests that HA basalts may be a widespread phenomenon on the Moon. Knowing the distribution of HA Mare basalts on the lunar surface has significance for models of the origin and the evolution of the Lunar Magma Ocean. Surface exposures of HA basalts can be detected with compositional remote sensing data from Lunar Prospector Gamma Ray Spectrometer and Clementine. We searched the lunar surface for regions of interest (ROIs) that correspond to the intersection of three compositional constraints taken from values of sampled HA basalts: 12–18 wt% FeO, 1.5–5 wt% TiO2, and 0–4 ppm Th. We then determined the “true” (unobscured by regolith) composition of basalt units by analyzing the rims and proximal ejecta of small impacts (0.4–4 km in diameter) into the Mare surface of these ROIs. This paper focuses on two ROIs that are the best candidates for sources of sampled HA basalts: Mare Fecunditatis, the landing site of Luna 16; and northern Mare Imbrium, hypothesized origin of the Apollo 14 HA basalts. We demonstrate our technique's ability for delineating discrete basalt units and determining which is the best compositional match to the HA basalts sampled by each mission. We identified two units in Mare Fecunditatis that spectrally resemble HA basalts, although only one unit (Iltm) is consistent with the compositional and relative age of the Luna 16 HA samples. Northern Mare Imbrium also reveals two units that are within the compositional constraints of HA basalts, with one (Iltm) best matching the composition of the basalts sampled by Apollo 14.
Georgiana Y. Kramer - One of the best experts on this subject based on the ideXlab platform.
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Distinguishing high‐alumina Mare basalts using Clementine UVVIS and Lunar Prospector GRS data: Mare Moscoviense and Mare Nectaris
Journal of Geophysical Research, 2008Co-Authors: Georgiana Y. Kramer, Bradley L. Jolliff, Clive R. NealAbstract:[1] High-alumina (HA) Mare basalts are a unique group of the lunar sample collection. Sample geochemistry indicates that these basalts are derived from sources composed of late-stage cumulates from the Lunar Magma Ocean (LMO). Their aluminous nature suggests their sources contained significant plagioclase, which has implications regarding the efficiency of plagioclase separation from earlier forming, mafic cumulates in the LMO to form the anorthositic lunar crust, and hence the heterogeneity of the lunar mantle. The Apollo and Luna missions sampled HA basalts from four different locations that are separated by 80 equatorial degrees (∼2400 km). Radiometric age dating of these samples demonstrates aluminous basaltic volcanism spanned over 1 billion years, suggesting HA basalts may be more prevalent on the Moon than implied by the sample population. Knowing their global occurrence would ultimately enhance our understanding of lunar evolution. Aluminous Mare basalts occupy a unique location in Th-FeO compositional space that suggests they can be identified using global remote-sensing data of the Moon. We present our approach for distinguishing exposures of HA basalts using Clementine ultraviolet-visible-infrared (UVVIS) and Lunar Prospector Gamma Ray Spectrometer (LP-GRS) data with constraints based on the FeO, TiO2, and Th abundances of Apollo and Luna HA samples. We identified 34 regions of interest (ROIs) where HA basalts could be a prominent component of the lunar surface. By analyzing the rims and proximal ejecta from small impacts (0.4–4 km in diameter) into the Mare surface we characterized compositionally distinct basaltic units that make up the Mare and thus determined which units represent HA basalt lavas. The results were used to generate maps that depict discrete Mare units and classify their general basalt type. Here we focus on two ROIs: Mare Moscoviense and Mare Nectaris. Mare Moscoviense is composed of four basaltic units, two of which are HA candidates. Clementine UVVIS data of Mare Nectaris show evidence of up to three Mare basalt units. One is the remnants of a mid-Ti unit that capped earlier low-Ti flows. The majority of the basin is filled by a compositionally indistinguishable low-Fe, low-Ti basalt. However, spectral profiles suggest there are two units. Regardless, the units both fit the criteria for a HA basalt.
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distinguishing high alumina Mare basalts using clementine uvvis and lunar prospector grs data Mare moscoviense and Mare nectaris
Journal of Geophysical Research, 2008Co-Authors: Georgiana Y. Kramer, Bradley L. Jolliff, Clive R. NealAbstract:[1] High-alumina (HA) Mare basalts are a unique group of the lunar sample collection. Sample geochemistry indicates that these basalts are derived from sources composed of late-stage cumulates from the Lunar Magma Ocean (LMO). Their aluminous nature suggests their sources contained significant plagioclase, which has implications regarding the efficiency of plagioclase separation from earlier forming, mafic cumulates in the LMO to form the anorthositic lunar crust, and hence the heterogeneity of the lunar mantle. The Apollo and Luna missions sampled HA basalts from four different locations that are separated by 80 equatorial degrees (∼2400 km). Radiometric age dating of these samples demonstrates aluminous basaltic volcanism spanned over 1 billion years, suggesting HA basalts may be more prevalent on the Moon than implied by the sample population. Knowing their global occurrence would ultimately enhance our understanding of lunar evolution. Aluminous Mare basalts occupy a unique location in Th-FeO compositional space that suggests they can be identified using global remote-sensing data of the Moon. We present our approach for distinguishing exposures of HA basalts using Clementine ultraviolet-visible-infrared (UVVIS) and Lunar Prospector Gamma Ray Spectrometer (LP-GRS) data with constraints based on the FeO, TiO2, and Th abundances of Apollo and Luna HA samples. We identified 34 regions of interest (ROIs) where HA basalts could be a prominent component of the lunar surface. By analyzing the rims and proximal ejecta from small impacts (0.4–4 km in diameter) into the Mare surface we characterized compositionally distinct basaltic units that make up the Mare and thus determined which units represent HA basalt lavas. The results were used to generate maps that depict discrete Mare units and classify their general basalt type. Here we focus on two ROIs: Mare Moscoviense and Mare Nectaris. Mare Moscoviense is composed of four basaltic units, two of which are HA candidates. Clementine UVVIS data of Mare Nectaris show evidence of up to three Mare basalt units. One is the remnants of a mid-Ti unit that capped earlier low-Ti flows. The majority of the basin is filled by a compositionally indistinguishable low-Fe, low-Ti basalt. However, spectral profiles suggest there are two units. Regardless, the units both fit the criteria for a HA basalt.
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Searching for high alumina Mare basalts using Clementine UVVIS and Lunar Prospector GRS data: Mare Fecunditatis and Mare Imbrium
Icarus, 2008Co-Authors: Georgiana Y. Kramer, Bradley L. Jolliff, Clive R. NealAbstract:Abstract In the context of sample evidence alone, the high-alumina (HA) basalts appear to be an unique, and rare variety of Mare basalt. In addition to their distinct chemistry, radiometric dating reveals these basalts to be among the oldest sampled Mare basalts. Yet, HA basalts were sampled by four missions spanning a lateral range of ∼2400 km, with ages demonstrating that aluminous volcanism lasted at least 1 billion years. This evidence suggests that HA basalts may be a widespread phenomenon on the Moon. Knowing the distribution of HA Mare basalts on the lunar surface has significance for models of the origin and the evolution of the Lunar Magma Ocean. Surface exposures of HA basalts can be detected with compositional remote sensing data from Lunar Prospector Gamma Ray Spectrometer and Clementine. We searched the lunar surface for regions of interest (ROIs) that correspond to the intersection of three compositional constraints taken from values of sampled HA basalts: 12–18 wt% FeO, 1.5–5 wt% TiO2, and 0–4 ppm Th. We then determined the “true” (unobscured by regolith) composition of basalt units by analyzing the rims and proximal ejecta of small impacts (0.4–4 km in diameter) into the Mare surface of these ROIs. This paper focuses on two ROIs that are the best candidates for sources of sampled HA basalts: Mare Fecunditatis, the landing site of Luna 16; and northern Mare Imbrium, hypothesized origin of the Apollo 14 HA basalts. We demonstrate our technique's ability for delineating discrete basalt units and determining which is the best compositional match to the HA basalts sampled by each mission. We identified two units in Mare Fecunditatis that spectrally resemble HA basalts, although only one unit (Iltm) is consistent with the compositional and relative age of the Luna 16 HA samples. Northern Mare Imbrium also reveals two units that are within the compositional constraints of HA basalts, with one (Iltm) best matching the composition of the basalts sampled by Apollo 14.
M Anand - One of the best experts on this subject based on the ideXlab platform.
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late delivery of chondritic hydrogen into the lunar mantle insights from Mare basalts
Earth and Planetary Science Letters, 2013Co-Authors: Romain Tartese, M AnandAbstract:Recent analytical advances have enabled first successful in-situ detection of water (measured as OH) in lunar volcanic glasses, and, melt inclusions and minerals from Mare basalts. These in-situ measurements in lunar materials, coupled with observations made by orbiting spacecraft missions have challenged the traditional view of the Moon as an anhydrous body. By synthesizing and modeling of previously published data on OH contents and H isotope compositions of apatite from Mare basalts, we demonstrate that a model of hydrogen delivery into the lunar interior by late accretion of chondritic materials adequately accounts for the measured “water” content and its hydrogen isotopic composition in Mare basalts. In our proposed model, “water” in the lunar interior was mostly constituted by hydrogen, delivered by the late accretion of chondrite-type materials. Our model is also consistent with previously proposed models to account for other geochemical characteristics of the lunar samples.
