Diet Selection by a Lizard Ant-Specialist in an Urban System Bereft of Preferred Prey

Ramakrishnan, Shantini; Wolf, Alexander J.; Hellgren, Eric C.; Moody, Raymond W.; Bogosian, Victor

doi:10.1670/16-072

Cited by 10 publications

(13 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Whitford and Bryant (1979) demonstrated irrefutably that Texas horned lizards are food limited and exhibit a pronounced preference for harvester ants (Pogonomyrmex spp.). Although the extent of this dietary dependence is subject to variation (e.g., Milne and Milne, 1950;Ramakrishnan et al, 2018), harvester ant densities and colony sizes are geographically variable (MacMahon et al, 2000;Warburg et al, 2017). In fact, harvester ant densities were found to be far greater at a central Texas site compared to a southern New Mexico site (Whiting et al, 1993).…”

Section: Discussionmentioning

confidence: 99%

Latitudinal Variation in Life History Reveals a Reproductive Advantage in the Texas Horned Lizard (Phrynosoma cornutum)

Hughes

Meshaka²,

Lieb

et al. 2019

Copeia

View full text Add to dashboard Cite

doi: bioRxiv preprint Geographically widespread species that occupy many thermal environments provide testable models for understanding the evolution of life-history responses to latitude, yet studies that draw range-wide conclusions using descriptive data from populations in the core of a species' distribution can overlook meaningful inter-population variation. The phrynosomatid lizard Phrynosoma cornutum spans an extensive latitudinal distribution in North America and has been well-studied in connection with life-history evolution, yet populations occupying the most northern and coldest areas within its range were absent from previous examinations. We tested genus-wide models and challenged species-specific findings on the evolution of the life-history strategy for P. cornutum using populations at the northern edge of its geographic range and comparative material from farther south.Multivariate analyses revealed that egg dimensions decreased with clutch size, suggestive of a previously unrecognized tradeoff between egg size and egg number in this species.Interestingly, reproductive traits of females with shelled eggs did not covary with latitude, yet we found that populations at the highest latitudes typified several traits of the genus and for the species, including a model for Phrynosoma of large clutches and delayed reproduction. A significant deviation from earlier findings is that we detected latitudinal variation in clutch size. This finding, although novel, is unsurprising given the smaller body sizes from northern populations and the positive relationship between clutch size and body size. Intriguing, however, was that the significant reduction in clutch size persisted when female body size was held constant, indicating a reproductive disadvantage to living at higher latitudes. We discuss the possible selective pressures that may have resulted in the diminishing returns on reproductive output at higher latitudes. Our findings highlight the .

show abstract

Section: Discussionmentioning

confidence: 99%

Latitudinal Variation in Life History Reveals a Reproductive Advantage in the Texas Horned Lizard (Phrynosoma cornutum)

Hughes

Meshaka²,

Lieb

et al. 2019

Copeia

View full text Add to dashboard Cite

show abstract

“…Dominant vegetation types are a mixture of native and non‐native grassland species (little bluestem [ Schizachyrium scoparium ], big bluestem [ Andropogon gerardii ], indiangrass [ Sorghastrum nutans ], Maximilian sunflower [ Helianthus maximiliani ], and side oats grama [ Bouteloua curtipendula ]) interspersed with patches of eastern red cedar ( Juniperus virginiana ), 2 small ponds, and gravel paths (Moody et al 2007). Harvester ants have not been documented to date at our study site (Ramakrishnan et al 2018). Management activities are underway on and around WR3 specifically designed to connect Texas horned lizard habitat, such as prescribed burning and prairie restoration.…”

Section: Study Areamentioning

confidence: 90%

“…The climate at TAFB is seasonal and classified officially as warm subhumid with pronounced day-to-day changes and more gradual changes across 4 seasons: spring (Mar-Jun), (Moody et al 2007). Harvester ants have not been documented to date at our study site (Ramakrishnan et al 2018). Management activities are underway on and around WR3 specifically designed to connect Texas horned lizard habitat, such as prescribed burning and prairie restoration.…”

Section: Study Areamentioning

confidence: 95%

“…A population of Texas horned lizards in Oklahoma occurs on Tinker Air Force Base (TAFB) in Midwest City, Oklahoma (Endriss et al 2007;Moody et al 2007;Wolf et al 2013Wolf et al , 2015Ramakrishnan et al 2018). Research on Texas horned lizards at TAFB has continued for the last 17 years, resulting in baseline understanding of this population's natural history and dynamics (Moody et al 2007, Bogosian 2010, Bogosian et al 2012, Wolf et al 2014, Mook et al 2017.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Survivorship and Spatial Patterns of an Urban Population of Texas Horned Lizards

et al. 2021

Self Cite

View full text Add to dashboard Cite

Habitat fragmentation has negative consequences on threatened and endangered species by creating isolated populations. The Texas horned lizard (Phrynosoma cornutum) is experiencing population declines and localized extirpations throughout its range and has been classified as a species of greatest conservation need in Oklahoma, USA. Younger age classes have been poorly studied but may be vital to the stability of remaining populations. To address gaps in knowledge concerning subadult (hatchling and juvenile) morphometrics, survivorship, and home range sizes, we studied 2 cohorts of subadults, for 2 years each, covering their hatching and juvenile years (2016)(2017)(2018)(2019). We used a combination of radio-telemetry and novel harmonic radar methodology to study a closed population of Texas horned lizards in 15 ha of native grassland at Tinker Air Force Base, Oklahoma. Population abundance for adults and juveniles was estimated as 56.5 ± 5.5 lizards and density as 7.96 lizards/ha. Our lowest estimates of survival indicated an average survival probability for the hatchling life stage of 0.285 (95% CI = 0.15-0.44), which is lower than for adults on the site. Average home range size increased from hatchling to adult life stages. Our results will have an immediate effect on the planning and assessment of ongoing headstart and management programs for Texas horned lizards.

show abstract

“…While we do not have data on the insect abundance on the dunes, the most common prey eaten ( Dorymyrmex ) were also the most commonly observed insect on the dunes (EJM unpublished data). Previous studies have found that P. cornutum will consume other ants and insects in the absence of harvester ants 84–86 . A study on the desert horned lizard ( Phrynosoma platyrhinos ) suggests that horned lizards are opportunistic feeders that consume ants based on availability and size instead of specifically preferring harvester ants 87 .…”

Section: Discussionmentioning

confidence: 98%

Genetics, morphology and diet of introduced populations of the ant-eating Texas Horned Lizard (Phrynosoma cornutum)

Heuring

Barber

Rains

et al. 2019

Sci Rep

View full text Add to dashboard Cite

Introduced species can diverge from their source population when they become established in a new ecosystem. The Texas Horned Lizard ( Phrynosoma cornutum ) is native to the western United States (US) and was historically introduced to several locations in the southeastern US. We studied three introduced populations in South Carolina, US to determine if they exhibit dietary, morphological and genetic divergence from the native western US populations. We expected little divergence from western populations because P. cornutum is a specialist whose biology is largely shaped by its diet of Pogonomyrmex harvester ants. We show that the introduced populations have mixed ancestry between south Texas and more northern areas and experienced founder effects and genetic bottlenecks resulting in decreased genetic diversity. South Carolina lizards primarily consume ants (94%), but surprisingly, they did not eat harvester ants. Introduced lizards primarily eat Dorymyrmex ants, but each introduced population complements Dorymyrmex with significantly different amounts of other species of ants, insects and plant matter. Introduced populations have smaller body size and have different limb and head shapes compared to western populations. This study demonstrates successful persistence of an introduced vertebrate that may be attributed to phenotypic change, even in the face of reduced genetic diversity.

show abstract

Diet Selection by a Lizard Ant-Specialist in an Urban System Bereft of Preferred Prey

Cited by 10 publications

References 38 publications

Latitudinal Variation in Life History Reveals a Reproductive Advantage in the Texas Horned Lizard (Phrynosoma cornutum)

Latitudinal Variation in Life History Reveals a Reproductive Advantage in the Texas Horned Lizard (Phrynosoma cornutum)

Survivorship and Spatial Patterns of an Urban Population of Texas Horned Lizards

Genetics, morphology and diet of introduced populations of the ant-eating Texas Horned Lizard (Phrynosoma cornutum)

Contact Info

Product

Resources

About