Asynchronous eye closure as an anti-predator behavior in the western fence lizard (Sceloporus occidentalis)

Christian G. Mathews, John A. Lesku, Steven L. Lima, Charles J. Amlaner

    Research output: Contribution to journalArticle

    33 Citations (Scopus)

    Abstract

    Asynchronous eye closure (ASEC), one eye open while the other is closed, is a behavior observed in birds, some aquatic mammals, and reptiles. In birds and aquatic mammals, ASEC is associated with unihemispheric sleep wherein the cerebral hemisphere contralateral to (i.e. neurologically connected to) the closed eye sleeps while the other cerebral hemisphere remains awake with its associated eye open and functional. Evidence from birds suggests that ASEC is an important anti-predator adaptation to mediate the trade-off between the need to remain vigilant and the need to sleep. However, the anti-predator correlates of ASEC remain largely unstudied in other animals. Here, we present behavioral evidence that ASEC in reptiles is also an anti-predator adaptation used in response to an increase in the risk of predation. ASEC was measured in captive western fence lizards (Sceloporus occidentalis) individually exposed to three experimental treatments: (1) an empty terrarium, (2) a terrarium housing a novel moving object, and (3) a terrarium housing a live predator (snake). Predator exposure elicited significantly higher levels of vigilance, mostly due to an increase in ASEC. This increase in ASEC came largely at the expense of synchronous eye closure (both eyes closed). Lizards in ASEC also showed a strong tendency to orient their open eye in the direction of the predator. We suggest that lizards engaged in ASEC are sleeping unihemispherically and are thus able to maintain a level of vigilance concurrent with sleep.

    Original languageEnglish
    Pages (from-to)286-292
    Number of pages7
    JournalEthology
    Volume112
    Issue number3
    DOIs
    StatePublished - 1 Mar 2006

    Fingerprint

    Sceloporus occidentalis
    Lizards
    lizard
    eyes
    predator
    predators
    sleep
    Sleep
    Birds
    vigilance
    Reptiles
    Cerebrum
    bird
    reptile
    reptiles
    lizards
    Mammals
    mammals

    Cite this

    Mathews, Christian G. ; Lesku, John A. ; Lima, Steven L. ; Amlaner, Charles J. / Asynchronous eye closure as an anti-predator behavior in the western fence lizard (Sceloporus occidentalis). In: Ethology. 2006 ; Vol. 112, No. 3. pp. 286-292.
    @article{3ff17c54655a46a1b9ef0f53071c3a32,
    title = "Asynchronous eye closure as an anti-predator behavior in the western fence lizard (Sceloporus occidentalis)",
    abstract = "Asynchronous eye closure (ASEC), one eye open while the other is closed, is a behavior observed in birds, some aquatic mammals, and reptiles. In birds and aquatic mammals, ASEC is associated with unihemispheric sleep wherein the cerebral hemisphere contralateral to (i.e. neurologically connected to) the closed eye sleeps while the other cerebral hemisphere remains awake with its associated eye open and functional. Evidence from birds suggests that ASEC is an important anti-predator adaptation to mediate the trade-off between the need to remain vigilant and the need to sleep. However, the anti-predator correlates of ASEC remain largely unstudied in other animals. Here, we present behavioral evidence that ASEC in reptiles is also an anti-predator adaptation used in response to an increase in the risk of predation. ASEC was measured in captive western fence lizards (Sceloporus occidentalis) individually exposed to three experimental treatments: (1) an empty terrarium, (2) a terrarium housing a novel moving object, and (3) a terrarium housing a live predator (snake). Predator exposure elicited significantly higher levels of vigilance, mostly due to an increase in ASEC. This increase in ASEC came largely at the expense of synchronous eye closure (both eyes closed). Lizards in ASEC also showed a strong tendency to orient their open eye in the direction of the predator. We suggest that lizards engaged in ASEC are sleeping unihemispherically and are thus able to maintain a level of vigilance concurrent with sleep.",
    author = "Mathews, {Christian G.} and Lesku, {John A.} and Lima, {Steven L.} and Amlaner, {Charles J.}",
    year = "2006",
    month = "3",
    day = "1",
    doi = "10.1111/j.1439-0310.2006.01138.x",
    language = "English",
    volume = "112",
    pages = "286--292",
    journal = "Ethology",
    issn = "0179-1613",
    publisher = "Wiley-Blackwell Publishing Ltd",
    number = "3",

    }

    Asynchronous eye closure as an anti-predator behavior in the western fence lizard (Sceloporus occidentalis). / Mathews, Christian G.; Lesku, John A.; Lima, Steven L.; Amlaner, Charles J.

    In: Ethology, Vol. 112, No. 3, 01.03.2006, p. 286-292.

    Research output: Contribution to journalArticle

    TY - JOUR

    T1 - Asynchronous eye closure as an anti-predator behavior in the western fence lizard (Sceloporus occidentalis)

    AU - Mathews, Christian G.

    AU - Lesku, John A.

    AU - Lima, Steven L.

    AU - Amlaner, Charles J.

    PY - 2006/3/1

    Y1 - 2006/3/1

    N2 - Asynchronous eye closure (ASEC), one eye open while the other is closed, is a behavior observed in birds, some aquatic mammals, and reptiles. In birds and aquatic mammals, ASEC is associated with unihemispheric sleep wherein the cerebral hemisphere contralateral to (i.e. neurologically connected to) the closed eye sleeps while the other cerebral hemisphere remains awake with its associated eye open and functional. Evidence from birds suggests that ASEC is an important anti-predator adaptation to mediate the trade-off between the need to remain vigilant and the need to sleep. However, the anti-predator correlates of ASEC remain largely unstudied in other animals. Here, we present behavioral evidence that ASEC in reptiles is also an anti-predator adaptation used in response to an increase in the risk of predation. ASEC was measured in captive western fence lizards (Sceloporus occidentalis) individually exposed to three experimental treatments: (1) an empty terrarium, (2) a terrarium housing a novel moving object, and (3) a terrarium housing a live predator (snake). Predator exposure elicited significantly higher levels of vigilance, mostly due to an increase in ASEC. This increase in ASEC came largely at the expense of synchronous eye closure (both eyes closed). Lizards in ASEC also showed a strong tendency to orient their open eye in the direction of the predator. We suggest that lizards engaged in ASEC are sleeping unihemispherically and are thus able to maintain a level of vigilance concurrent with sleep.

    AB - Asynchronous eye closure (ASEC), one eye open while the other is closed, is a behavior observed in birds, some aquatic mammals, and reptiles. In birds and aquatic mammals, ASEC is associated with unihemispheric sleep wherein the cerebral hemisphere contralateral to (i.e. neurologically connected to) the closed eye sleeps while the other cerebral hemisphere remains awake with its associated eye open and functional. Evidence from birds suggests that ASEC is an important anti-predator adaptation to mediate the trade-off between the need to remain vigilant and the need to sleep. However, the anti-predator correlates of ASEC remain largely unstudied in other animals. Here, we present behavioral evidence that ASEC in reptiles is also an anti-predator adaptation used in response to an increase in the risk of predation. ASEC was measured in captive western fence lizards (Sceloporus occidentalis) individually exposed to three experimental treatments: (1) an empty terrarium, (2) a terrarium housing a novel moving object, and (3) a terrarium housing a live predator (snake). Predator exposure elicited significantly higher levels of vigilance, mostly due to an increase in ASEC. This increase in ASEC came largely at the expense of synchronous eye closure (both eyes closed). Lizards in ASEC also showed a strong tendency to orient their open eye in the direction of the predator. We suggest that lizards engaged in ASEC are sleeping unihemispherically and are thus able to maintain a level of vigilance concurrent with sleep.

    UR - http://www.scopus.com/inward/record.url?scp=33645022547&partnerID=8YFLogxK

    U2 - 10.1111/j.1439-0310.2006.01138.x

    DO - 10.1111/j.1439-0310.2006.01138.x

    M3 - Article

    AN - SCOPUS:33645022547

    VL - 112

    SP - 286

    EP - 292

    JO - Ethology

    JF - Ethology

    SN - 0179-1613

    IS - 3

    ER -