| 1. |
- Kanai, M, et al.
(author)
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- 2023
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swepub:Mat__t
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| 2. |
- Niemi, MEK, et al.
(author)
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- 2021
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swepub:Mat__t
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| 3. |
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| 4. |
- Rowan, John, et al.
(author)
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Early Pleistocene large mammals from Maka’amitalu, Hadar, lower Awash Valley, Ethiopia
- 2022
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In: PeerJ. - Corte Medera : PeerJ. - 2167-8359. ; 10, s. e13210-e13210
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Journal article (peer-reviewed)abstract
- The Early Pleistocene was a critical time period in the evolution of eastern Africanmammal faunas, but fossil assemblages sampling this interval are poorly known fromEthiopia’s Afar Depression. Field work by the Hadar Research Project in theBusidima Formation exposures (~2.7–0.8 Ma) of Hadar in the lower Awash Valley,resulted in the recovery of an early Homo maxilla (A.L. 666-1) with associated stonetools and fauna from the Maka’amitalu basin in the 1990s. These assemblages aredated to ~2.35 Ma by the Bouroukie Tuff 3 (BKT-3). Continued work by the HadarResearch Project over the last two decades has greatly expanded the faunal collection.Here, we provide a comprehensive account of the Maka’amitalu large mammals(Artiodactyla, Carnivora, Perissodactyla, Primates, and Proboscidea) and discusstheir paleoecological and biochronological significance. The size of the Maka’amitalu assemblage is small compared to those from the Hadar Formation (3.45–2.95 Ma)and Ledi-Geraru (2.8–2.6 Ma) but includes at least 20 taxa. Bovids, suids, andTheropithecus are common in terms of both species richness and abundance, whereascarnivorans, equids, and megaherbivores are rare. While the taxonomic compositionof the Maka’amitalu fauna indicates significant species turnover from the HadarFormation and Ledi-Geraru deposits, turnover seems to have occurred at a constantrate through time as taxonomic dissimilarity between adjacent fossil assemblages isstrongly predicted by their age difference. A similar pattern characterizes functionalecological turnover, with only subtle changes in dietary proportions, body sizeproportions, and bovid abundances across the composite lower Awash sequence.Biochronological comparisons with other sites in eastern Africa suggest that the taxarecovered from the Maka’amitalu are broadly consistent with the reported age of theBKT-3 tuff. Considering the age of BKT-3 and biochronology, a range of 2.4–1.9 Mais most likely for the faunal assemblage.
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| 5. |
- De, Kishalay, et al.
(author)
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The Zwicky Transient Facility Census of the Local Universe. I. Systematic Search for Calcium-rich Gap Transients Reveals Three Related Spectroscopic Subclasses
- 2020
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In: Astrophysical Journal. - : American Astronomical Society. - 0004-637X .- 1538-4357. ; 905:1
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Journal article (peer-reviewed)abstract
- Using the Zwicky Transient Facility alert stream, we are conducting a large spectroscopic campaign to construct a complete, volume-limited sample of transients brighter than 20 mag, and coincident within 100 '' of galaxies in the Census of the Local Universe catalog. We describe the experiment design and spectroscopic completeness from the first 16 months of operations, which have classified 754 supernovae. We present results from a systematic search for calcium-rich gap transients in the sample of 22 low-luminosity (peak absolute magnitude M > -17), hydrogen-poor events found in the experiment. We report the detection of eight new events, and constrain their volumetric rate to greater than or similar to 15% +/- 5% of the SN Ia rate. Combining this sample with 10 previously known events, we find a likely continuum of spectroscopic properties ranging from events with SN Ia-like features (Ca-Ia objects) to those with SN Ib/c-like features (Ca-Ib/c objects) at peak light. Within the Ca-Ib/c events, we find two populations distinguished by their red (g - r approximate to 1.5 mag) or green (g - r approximate to 0.5 mag) colors at the r-band peak, wherein redder events show strong line blanketing features and slower light curves (similar to Ca-Ia objects), weaker He lines, and lower [Ca II]/[O I] in the nebular phase. We find that all together the spectroscopic continuum, volumetric rates, and striking old environments are consistent with the explosive burning of He shells on low-mass white dwarfs. We suggest that Ca-Ia and red Ca-Ib/c objects arise from the double detonation of He shells, while green Ca-Ib/c objects are consistent with low-efficiency burning scenarios like detonations in low-density shells or deflagrations.
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| 6. |
- Reed, Kaye E., et al.
(author)
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Geology, Fauna, and Paleoenvironmental Reconstructions of the Makapansgat Limeworks Australopithecus africanus-Bearing Paleo-Cave
- 2022
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In: African Palaeoecology and Human Evolution. - Cham : Springer Nature. ; , s. 66-81
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Book chapter (peer-reviewed)abstract
- The Makapansgat Valley is located in Limpopo Province, South Africa (Figure 7.1), and is the northernmost of the South African australopithecine fossil sites. Hominin fossils were first recovered there in 1947, but the history and significance of the valley dates to the nineteenth century. The name of the site and valley derives from the Historic, or Gwasa, Cave at the head of the valley, which was the location of a siege in 1854 (Naidoo, 1987; Esterhuysen et al., 2008) on local Ndebele tribespeople by a Boer Commando in retaliation for two massacres – themselves retaliation for raids for ivory and slave labor by the Boer on Ndebele villages. The chief was Mokopane, and the cave became known as “Makapan’s Cave” or -gat in Afrikaans.
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