The comparative biomechanics of an ophidian defensive behaviour: head triangulation in hognose snake (<i>Heterodon</i>) and an egg‐eating snake (<i>Dasypeltis</i>)

Young, Bruce A.; Lalor, Julia; Solomon, Joseph H.

doi:10.1111/j.1469-7998.1999.tb01193.x

Cited by 8 publications

(2 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For example, coral snakes employ aposematic colour displays, while a number of other species have evolved neck flattening or "hooding" strategies, most notably known in cobras (Carpenter & Ferguson, 1977;Young, 1997;Young et al, 1999).…”

Section: Introductionmentioning

confidence: 99%

The neck flattening defensive behaviour in snakes: First record of hooding in the South American colubrid genus Philodryas

Jara

Pincheira‐Donoso

2015

Animal Biol

View full text Add to dashboard Cite

Animal species have evolved a remarkable diversity of defensive phenotypic strategies aimed to deceive predators and other forms of danger. By relying on deception, these adaptations increase the chances of avoiding physical contact that may otherwise have very high fitness costs. One such deceptive behaviour is the popularly-known neck flattening, or "hooding", observed in some snakes. Hooding consists in the lateral expansion and dorso-ventral flattening of the neck, which creates the impression of a bigger opponent during confrontations. This trait is highly characteristic of cobras (Elapidae family). However, neck flattening is not exclusive to elapids, and has in fact been observed in a few other snake lineages, including some species of the families Lamprophiidae and Colubridae. Here, we present the first report of hooding behaviour in the South American colubrid genus Philodryas, based on field observations conducted on the Chilean species P. chamissonis (the longtailed snake). Our report adds to the few cases in which this deceptive behaviour has been observed in snakes outside the cobra family.

show abstract

Section: Introductionmentioning

confidence: 99%

The neck flattening defensive behaviour in snakes: First record of hooding in the South American colubrid genus Philodryas

Jara

Pincheira‐Donoso

2015

Animal Biol

View full text Add to dashboard Cite

show abstract

“…In this respect hooding is viewed as similar to a variety of other ophidian visual displays that involve inflation or expansion of head and/or neck (e.g. Young et al, 1999;Young et al, 2000) The visual significance of the hood is further demonstrated by the presence in some species of eye spots or similar patterns on the dorsal surface of the hood (e.g. Wall, 1921).…”

Section: Efficacy Of Hooding Displaysmentioning

confidence: 99%

The functional morphology of hooding in cobras

Young

Kardong

2010

Journal of Experimental Biology

View full text Add to dashboard Cite

SUMMARYMany snakes, particularly cobras, form as part of a defensive display, a hood, an active lateral expansion of their neck skin and underlying musculature and ribs. We identified muscle groups possibly involved in hooding based on their attachments on the specialized ribs of the neck. We then used a combination of morphology, kinematic analysis, morphometrics, electromyography and muscle stimulation to test hypotheses about the functional basis of hooding. We confirmed that hood protraction and erection is an active process that begins cranially and extends caudally, often in stages, through the combined action of several sets of muscles. One set of axial muscles (levator costae and supracostalis lateralis superior) coursing along a line of action to rib displacement are the prime erectors acting to lift the hood. However, a second set of muscles connecting ribs to skin primarily keep the skin taut, rather than to displace the ribs relative to the vertebrae. A third set of muscles coursing between ribs function primarily to transmit forces between adjacent ribs rather than to move ribs. The maintenance of the erect hood requires continued muscle activity. Hood relaxation is due to both active muscle contraction of a fourth set of axial muscles and to passive recoil events in the costovertebral ligaments. The shape of the fully erect hood is reflective of the morphometrics of the underlying ribs, while the duration and kinematics of hood erection and relaxation are related to the behavioral context of the display.

show abstract

Comments on Guimarães & Sawaya. Pretending to be venomous: is a snake's head shape a trustworthy signal to a predator?

Valkonen

Mappes

2011

J. Trop. Ecol.

View full text Add to dashboard Cite

Several species of non-venomous snake are known to flatten their heads when disturbed, and this behaviour has been suggested to be a mimicry of vipers (Arnold & Ovenden 2002, Hailey & Davies 1986, Young et al. 1999). Using plasticine models, Guimarães & Sawaya (2011) tested the antipredatory function of a triangular head shape in snakes. Their article presents the first published empirical experiment testing the adaptive significance of vipers' triangular head shape. Guimarães & Sawaya (2011) found no support for the viper mimicry hypothesis. Accordingly, they concluded that ‘the shape of [the] head seemed not to confer advantage itself’. Although the use of plasticine models is a generally accepted method of testing predation pressure on snakes, we argue that the experiment may have failed to find the antipredatory function of triangulation due to the pooling of attacks by mammalian and avian predators. Mammals generally rely on olfactory cues during foraging. Plasticine has a strong odour which does not resemble the odour of any prey species. It is thus unlikely that mammals would treat snake replicas as true snakes.

show abstract

The comparative biomechanics of an ophidian defensive behaviour: head triangulation in hognose snake (Heterodon) and an egg‐eating snake (Dasypeltis)

Cited by 8 publications

References 7 publications

The neck flattening defensive behaviour in snakes: First record of hooding in the South American colubrid genus Philodryas

The neck flattening defensive behaviour in snakes: First record of hooding in the South American colubrid genus Philodryas

The functional morphology of hooding in cobras

Comments on Guimarães & Sawaya. Pretending to be venomous: is a snake's head shape a trustworthy signal to a predator?

Contact Info

Product

Resources

About