ArticleEvoDevo2011
Breaking evolutionary and pleiotropic constraints in mammals: On sloths, manatees and homeotic mutations.
Article in EvoDevo, 2011. The graph could read no effect estimate from its abstract, so it casts no vote on the map. An erratum has been issued. Cited by 39 papers.
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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Who cites it
39 citing papers in PubMed, 130 citations in OpenAlex.
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- Adaptive tail-length evolution in deer mice is associated with differential Hoxd13 expression in early development.Nature ecology & evolution · 2024Article
- The functional significance of aberrant cervical counts in sloths: insights from automated exhaustive analysis of cervical range of motion.Proceedings. Biological sciences · 2023Article
- Morphology of the Ventral Process of the Sixth Cervical Vertebra in Extinct and ExtantAnimals : an open access journal from MDPI · 2023Article
- Breaking the constraint on the number of cervical vertebrae in mammals: On homeotic transformations in lorises and pottos.Evolution & development · 2022Article
- Breaking constraint of mammalian axial formulae.Nature communications · 2022Article
- The Core Concepts, Competencies, and Grand Challenges of Comparative Vertebrate Anatomy and Morphology.Integrative organismal biology (Oxford, England) · 2022Article
- Correction to: Breaking evolutionary and pleiotropic constraints in mammals: on sloths, manatees and homeotic mutations.EvoDevo · 2021Article
- Limb positioning and initiation: An evolutionary context of pattern and formation.Developmental dynamics : an official publication of the American Association of Anatomists · 2021Review
- Article
- Exploring copy number variants in deceased fetuses and neonates with abnormal vertebral patterns and cervical ribs.Birth defects research · 2020Article
- Water lily (Proceedings of the National Academy of Sciences of the United States of America · 2020Article
- Arcuate foramen: "Anatomical variation shape or adaptation legacy?"Surgical and radiologic anatomy : SRA · 2019Article
- Embryonic and postembryonic development of the ornamental twin-tail goldfish.Developmental dynamics : an official publication of the American Association of Anatomists · 2019Article
- Bone cortical compactness in 'tree sloths' reflects convergent evolution.Journal of anatomy · 2018Article
Corrections and comments
- Erratum issued
Authors and funding
6 authors at 3 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundMammals as a rule have seven cervical vertebrae, except for sloths and manatees. Bateson proposed that the change in the number of cervical vertebrae in sloths is due to homeotic transformations. A recent hypothesis proposes that the number of cervical vertebrae in sloths is unchanged and that instead the derived pattern is due to abnormal primaxial/abaxial patterning.
resultsWe test the detailed predictions derived from both hypotheses for the skeletal patterns in sloths and manatees for both hypotheses. We find strong support for Bateson's homeosis hypothesis. The observed vertebral and rib patterns cannot be explained by changes in primaxial/abaxial patterning. Vertebral patterns in sloths and manatees are similar to those in mice and humans with abnormal numbers of cervical vertebrae: incomplete and asymmetric homeotic transformations are common and associated with skeletal abnormalities. In sloths the homeotic vertebral shift involves a large part of the vertebral column. As such, similarity is greatest with mice mutant for genes upstream of Hox.
conclusionsWe found no skeletal abnormalities in specimens of sister taxa with a normal number of cervical vertebrae. However, we always found such abnormalities in conspecifics with an abnormal number, as in many of the investigated dugongs. These findings strongly support the hypothesis that the evolutionary constraints on changes of the number of cervical vertebrae in mammals is due to deleterious pleitropic effects. We hypothesize that in sloths and manatees low metabolic and activity rates severely reduce the usual stabilizing selection, allowing the breaking of the pleiotropic constraints. This probably also applies to dugongs, although to a lesser extent.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.