The evolution of digit form in Gonatodes (Gekkota: Sphaerodactylidae) and its bearing on the transition from frictional to adhesive contact in gekkotans

@article{Russell2015TheEO,
  title={The evolution of digit form in Gonatodes (Gekkota: Sphaerodactylidae) and its bearing on the transition from frictional to adhesive contact in gekkotans},
  author={Anthony Patrick Russell and Joelle D Baskerville and Tony Gamble and Timothy E. Higham},
  journal={Journal of Morphology},
  year={2015},
  volume={276}
}
Although the phenomenon of adhesion in geckos has been intensively studied for over 200 years, our understanding of how the morphological apparatus associated with this arose is less clear. Indeed, whether or not all of the intricate morphological hierarchy that is implicated in the attachment and removal of the adhesive setae originated at the same time is unknown. To explore whether setae may have arisen prior to the other parts of this structural hierarchy, we undertook morphological… 

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References

SHOWING 1-10 OF 95 REFERENCES

Configuration of the setal fields of Rhoptropus (Gekkota: Gekkonidae): functional, evolutionary, ecological and phylogenetic implications of observed pattern

The configuration and dimensions of seven species of the gekkotan genus Rhoptropus, and an outgroup taxon, Chondrodactylus bibronii are examined to examine the pattern of configuration of the setae across the subdigital pads of these taxa and show that setal field configuration follows a predictable pattern.

Subdigital and subcaudal microornamentation in chamaeleonidae—A comparative study

It is shown that representatives from the chamaeleonid genera Calumma, Chamaeleo, Furcifer, and Trioceros feature highly developed setae that are species‐specific and similar on their feet and tail that rather resemble those in anoline and scincid lizards than the larger and branched setae of certain gecko species.

Experimental evidence for friction-enhancing integumentary modifications of chameleons and associated functional and evolutionary implications

Using a force transducer, it is demonstrated that the pilose skin of chameleons has a greater frictional coefficient than does the smooth skin of these animals, consistent with friction being generated as a result of side contact of the integumentary filaments.

Integrative Functional Morphology of the Gekkotan Adhesive System (Reptilia: Gekkota)1

  • A. Russell
  • Biology
    Integrative and comparative biology
  • 2002
The perpendicular and parallel preloads associated with setal attachment are now reconcilable with other morphological aspects of the gekkotan adhesive system—the lateral digital tendon complex and the vascular sinus network, respectively.

A new species of the genus Gonatodes Fitzinger, 1843 (Reptilia: Sphaerodactylidae) from central Guyana, northern South America

A new sphaerodactyl lizard of the genus Gonatodes Fitzinger, 1843 is described from the Iwokrama Forest Reserve, central Guyana, Guiana Shield, northern South America, which is known so far from the type locality only.

Subdigital Setae of Narrow‐Toed Geckos, Including a Eublepharid (Aeluroscalabotes felinus)

Evidence that members of Aeluroscalabotes felinus, the only arboreal eublepharids, possess subdigital setae up to 9 μm in length is presented, suggesting that the conditions leading to adhesive setae were probably present in the ancestors of all geckos, rather than arising multiple times within Gekkota.

Phylogenetic systematics of the genus Gonatodes (Squamata: Sphaerodactylidae) in the Guayana region, with description of a new species from Venezuela

The phylogenetic relationships and species boundaries of the diurnal geckos of the genus Gonatodes in the Guayana region are examined and it is suggested that the diversity of this genus in this region has resulted mostly from in situ diversification rather than multiple colonization events by different lineages.

A New Species of Gekkonid Lizard (Sphaerodactylinae: Gonatodes) from Guyana, South America

Abstract A new species of Gonatodes from central Guyana is described, illustrated, and named in honor of one of Guyana's outstanding citizens, Mr. Alexander Mendes. To date, the species is known only

Foraging behaviour of three sphaerodactylin geckos on Trinidad and Tobago (Sauria: Gekkonomorpha: Sphaerodactylini: Gonatodes)

The foraging mode of three sphaerodactylin species on Trinidad and Tobago, in May—June 2000, is examined and it is concluded that the three species are strict sit-and-wait' visual hunters that are dependent on light.

Comparative Ecology of Sympatric Gonatodes (Squamata: Gekkonidae) in the Western Amazon of Brazil

Differences in prey types appear to reflect differences in microhabitat use, and both species eat prey of the same size, and the possibility that niche differences between these Gonatodes species may be mediated by predators is suggested.
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