Claim · model-written summary
The pre-invasion Cycas micronesica populations on Rota showed considerable genetic variation.
- Taxon
- Cycas micronesica
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Cycas micronesicat0 - Outcome
- considerable genetic variatione0
Verbatim
t0“Cycas micronesica”
e0“The pre-invasion genetic structure of the host plant populations revealed considerable genetic variation and restricted gene flow among habitats and identified genetic clusters”
Title
Thomas E. Marler; Michael Calonje; Pablo Y. Rosiles-Loeza; et al. Discover Conservation 2026. doi:10.1007/s44353-026-00089-9
Other claims from this paper (19)
- Observation The pre-invasion Cycas micronesica populations showed restricted gene flow among habitats.
- Observation Genetic clusters representing the genetic variation of the species on Rota were identified in the pre-invasion populations.
- Observation There were 11,254 stems per ha in 2008.
- Observation 9.2% of the stems in 2008 were adult trees.
- Observation Seedlings rapidly reached 100% mortality.
- Observation There were 149 stems per ha in 2023.
- Observation All stems (100%) in 2023 were adult trees.
- Observation The native cycad population reached 98.6% mortality of the entire population within a 15-year span.
- Observation The adult tree population reached 85.6% mortality within a 15-year span.
- Observation Mean stem height was 30 cm in 2008.
- Observation Mean stem height gradually increased each year, reaching 245 cm in 2023, attributed to selective mortality of the small plants.
- Observation Mean leaf number per adult tree was 83 in 2008.
- Observation Mean leaf number per adult tree abruptly declined to a low of 8 in 2013.
- Observation Mean leaf number per adult tree then gradually increased to 20 in 2023.
- Observation Incidence of the herbivore rapidly increased to a peak in 2011.
- Observation Herbivore incidence then stabilized at about 40% to 50% of the soft organ surfaces.
- Observation Invasion by A. yasumatsui caused selective mortality of the smallest plants in the insular cycad population.
- Association Population-level mortality of the Rota cycad was more rapid than in the prior invasion of nearby Guam.
- Observation The authors conclude that the geographically separated and genetically isolated populations remain highly vulnerable to localized extirpations.