Limbs in whales and limblessness in other vertebrates: mechanisms of evolutionary and developmental transformation and loss

  title={Limbs in whales and limblessness in other vertebrates: mechanisms of evolutionary and developmental transformation and loss},
  author={Lars Bejder and Brian K. Hall},
  journal={Evolution \& Development},
We address the developmental and evolutionary mechanisms underlying fore- and hindlimb development and progressive hindlimb reduction and skeletal loss in whales and evaluate whether the genetic, developmental, and evolutionary mechanisms thought to be responsible for limb loss in snakes "explain" loss of the hindlimbs in whales. [] Key Result Hindlimbs likely began to regress only after the ancestors of whales entered the aquatic environment: Hindlimb function was co-opted by the undulatory vertical axial…
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  • R. Lande
  • Biology
    Evolution; international journal of organic evolution
  • 1978
The pattern and rate of limb loss are investigated by reviewing data from paleontology and comparative morphology, and theories of the reexpression of limb structures lost in mammalian evolution are considered in the light of facts from paleozoology and genetics.
Fossils, genes and the evolution of animal limbs
The origin and diversification of fins, wings and other structures, long a focus of palaeontology, can now be approached through developmental genetics.
Developmental mechanism involved in the embryonic reduction of limbs in reptiles.
  • A. Raynaud
  • Biology
    The International journal of developmental biology
  • 1990
Embryology, ultrastructural studies, chemical action on embryos and thymidine autoradiography of limb buds provide evidence that defects in the morphogenetic mechanisms involved in the development of limbs are responsible for the cessation of growth of the limb buds in serpentiform reptiles.
Morphogenesis of the rudimentary hind-limb of the glass snake (Ophisaurus apodus Pallas).
In the legless lizard, Ophisaurus apodus, the hind-limb primordium appears on the caudal extremity of the Wolffian ridge at an early stage in the development of the embryo and starts to regress at this point, due to the degeneration of the apical ridge.
Anatomy and relationships of Pachyrhachis problematicus, a primitive snake with hindlimbs
Pachyrhachis provides additional support for the hypothesis that snakes are most closely related to Cretaceous marine lizards (mosasauroids), and is shown to be the most primitive snake, and the sister–group to all other snakes.
Hox genes and the evolution of vertebrate axial morphology.
A comparative study of the developmental patterns of homeobox gene expression and developmental morphology between animals that have homologous regulatory genes but different morphologies, which contributes a mechanistic level to the assumed homology of these regions in vertebrates.
Whale Origins as a Poster Child for Macroevolution
Although Darwin didn’t have the details right—bears did not evolve into whales—his basic point was correct: The authors can now show that whales are in fact hoofed mammals that took to sea.
On the development of Cetacean extremities: II. Morphogenesis and histogenesis of the flippers in the spotted dolphin (Stenella attenuata).
The aim of this study is to describe the course of the development of flippers in the spotted dolphin (Stenella attenuata) and compare its features with other similar species from an evolutionary perspective.
Limb-somite relationship: origin of the limb musculature.
The possible existence of juxtaposed and interdigitated myogenic and tendinogenic compartments is discussed in view of the dissimilarity between the results of the two kinds of heterospecific recombinations.