Habitat Specific Growth Rate Adaptation in Oysters During Early Bartonian: Effects of High Temperature and Low Seasonality in the Indian Palaeotropics
Open accessPublished version of a preprint
Abstract
Seasonally resolved palaeoclimate reconstructions of extreme climatic events, coupled with responses of contemporaneous organisms, offer valuable information for mitigating the future. The tropical position of the Indian subcontinent during the Middle Eocene Climatic Optimum (MECO ∼41 Ma), interrupting a general cooling trend, provides an ideal setting to investigate low‐latitude seasonality under hot climate conditions, considering the modern minimal seasonality in the tropics. To better understand the seasonality and its impact on shallow marine fauna, a high‐resolution multiproxy study is conducted on oyster specimens of the species Flemingostrea pseudoflemingi from the early Bartonian palaeo‐tropical Kutch Basin. Clumped isotope (Δ 47 ) thermometry combined with δ 18 O analyses from excellently preserved shell specimens suggest low seasonal temperature fluctuations (∼3°C) with a mean temperature of 34.4 ± 2.0°C (95% CI) in the warmer season and 31.4 ± 2.4°C in the months of highest rainfall. Oyster populations from distinct regions within the basin display varying sizes. Smaller variants, inhabiting a zone influenced by marine conditions (δ 18 O w : −0.2 ± 0.5‰ to 0.4 ± 1.0‰) experienced slower growth rates (∼18 μm/day) only during the warmer months. In contrast, larger variants, probably residing in a shallower environment prone to larger impact of evaporation and fluvial influence (δ 18 O w : −1.0 ± 0.8‰ to 1.0 ± 0.7‰), maintained a steady growth rate (∼58 μm/day) throughout the year. Although the observed low seasonality is similar to modern tropical settings of the Indian and Pacific Oceans, the significantly warmer temperature range necessitated growth adaptations in oyster populations, as nutrient availability in diverse habitats were critical to their growth.
The claims and statistics of this paper haven’t been checked yet.
Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.
Integrity signals
Registry
Cites
Statistics
Claims the paper makes
The claims and statistics of this paper haven’t been checked yet.
Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.
Self-check
Percentages, sums and reported differences re-computed from the paper’s own numbers.
The self-check needs the paper’s full text.
Cites
Equilibrium and nonequilibrium oxygen isotope effects in synthetic carbonates
Kim, S.-T., & O'Neil, J. R. (1997) · Geochimica et Cosmochimica Acta · doi:10.1016/s0016-7037(97)00169-5 · Cited by 2,558 · see citing works
Paleoclimate reconstruction using carbonate clumped isotope thermometry
Eiler, J. M. (2011) · Quaternary Science Reviews · doi:10.1016/j.quascirev.2011.09.001 · Cited by 436 · cited 1× · see citing works
“In contrast, locations 1 and 2, with δ 18 O w values between − 0.2‰ and 0.4‰, close to modern and modeled late Eocene tropical marine ranges, indicate a seawater dominated setting with limited freshwater influence (Figure 9). δ 18 O cc is influenced by δ 18 O w and temperature (Eiler, 2011).”
InfluentialBernasconi, S. M., Daëron, M., Bergmann, K. D., Bonifacie, M., Meckler, A. N., Affek, H. P., Anderson, N., Bajnai, D., Barkan, E., Beverly, E., et al. (2021) · Geochemistry Geophysics Geosystems · doi:10.1029/2020gc009588 · Cited by 340 · cited 4× · see citing works
“The Δ 47 raw data were processed with simultaneously measured ETH‐1, ETH‐2, and ETH‐3 standards, from which an empirical transfer function (ETF) was determined by plotting their raw values versus their published accepted values at the I‐CDES90 scale (Bernasconi et al., 2018, 2021).”
InfluentialSelf-citationAnderson, N. T., Kelson, J. R., Kele, S., Daëron, M., Bonifacie, M., Horita, J., Mackey, T. J., John, C. M., Kluge, T., Petschnig, P., et al. (2021) · Geophysical Research Letters · doi:10.1029/2020gl092069 · Cited by 323 · see citing works
Bernasconi, S. M., Müller, I. A., Bergmann, K. D., Breitenbach, S. F. M., Fernandez, A., Hodell, D. A., Jaggi, M., Meckler, A. N., Millan, I., & Ziegler, M. (2018) · Geochemistry, Geophysics, Geosystems · doi:10.1029/2017gc007385 · Cited by 301 · see citing works
Self-citationJohn, C. M., & Bowen, D. (2016) · Rapid Communications in Mass Spectrometry · doi:10.1002/rcm.7720 · Cited by 247 · see citing works
de Winter, N. J., Müller, I. A., Kocken, I. J., Thibault, N., Ullmann, C. V., Farnsworth, A., Lunt, D. J., Claeys, P., & Ziegler, M. (2021) · Communications Earth & Environment · doi:10.1038/s43247-021-00193-9 · Cited by 52 · see citing works
Self-citation
Flagged first, then by citations
- Authors
- Mitra, A., de Winter, N. J., Miloikovitch, T., Halder, K., Ledésert, B. A., Claeys, P., & Müller, I. A.
- Affiliations
- Vrije Universiteit Brussel (BE)
- Archaeology, Environmental Changes & Geo‐Chemistry (AMGC) Vrije Universiteit Brussel Brussels Belgium
- Presidency University (IN)
- Institut des Sciences de la Terre de Paris (FR)
- ORCID
- Venue
- Paleoceanography and Paleoclimatology
- Publisher
- American Geophysical Union (AGU)
- Published
- 2025-10
- Volume
- 40
- Issue
- 10
- Pages
- e2025PA005129
- ISSN
- 2572-4517 (ISSN-L)
- 2572-4525
- OpenAlex
- W4415131515
- Cited by
- 2
- References
- 7
- Citations by year
- 2026: 1 · 2025: 1
- FWCI
- 1.42
- Type
- journal article
- Language
- en
- Open access
- hybrid
- doi.org
- Licence
- Locations
- Paleoceanography and Paleoclimatology (publishedVersion, cc-by)
- VUBIR (Vrije Universiteit Brussel) (submittedVersion)
- HAL (submittedVersion, cc-by-nc-nd)
- Funders
- Horizon 2020 Framework Programme (945380)
- Topics
- Physical Sciences › Earth and Planetary Sciences › Paleontology › Paleontology and Stratigraphy of Fossils
- Physical Sciences › Earth and Planetary Sciences › Atmospheric Science › Geology and Paleoclimatology Research
- Physical Sciences › Earth and Planetary Sciences › Paleontology › Evolution and Paleontology Studies
- Keywords
- oysters, Bartonian, Middle Eocene Climatic Optimum, seasonal variation, high temperature, clumped isotope thermometry, oxygen isotopes, growth rate, habitat adaptation, Kutch Basin, tropical paleoclimate, evaporation, nutrient availability
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
What counts as a claim ›How we measure confidence ›How we check this ›
Are you an author, or do you see a problem with this page? Request a review
