The behavior and demographics of the naked mole-rat, Heterocephalus glaber.

The question of how eusociality evolved in insects has been a major question for evolutionary biology since Darwin. Recently, a mammal, the naked mole-rat, was discovered also to have queens and functionally sterile workers. From 1986 to 1990 I trapped, marked, and studied the demography and behavior of a wild population of over 2000 naked mole-rats in Meru National Park, Kenya. Sex ratios in wild colonies were male biased. However, higher mortality among small males resulted in female biased sex ratios among the larger members of the colony. Few phenotypic differences were found between the sexes and the reasons for higher mortality among small males were not discovered. Despite unusually high life spans reported for naked mole-rats in captivity (16 years or greater), attrition in wild colonies sometimes exceeded 60 percent in a single year. Such mortality is compensated at the colony level by extremely high reproductive rates. Mortality of queens was much lower than that of workers. Attrition in wild colonies may be due in large part to mortality, during colony maintenance and defense or failed attempts to disperse. Although others have argued that naked mole-rats only form new colonies by fissioning of existing colonies, I present evidence that pairs of mole-rats can found new colonies. Individual naked mole-rats also move about on the soil surface at times, perhaps in efforts to disperse. Discovery of eusociality in two new animal taxa in the past 15 years (Homoptera and Rodentia), suggests that the selective forces which have led to the evolution of eusociality in animals may have led to similar division of reproductive labor in the plant kingdom. Suggestions are made as to where to look for analogues of social behavior in the plant kingdom.Ph.D.Biological SciencesZoologyUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/128677/2/9123982.pd

Ingram_etal_dloop_MLtree

Maximum Likelihood tree file for Ingram et al Dloop sequences

Data from: Challenging the inbreeding hypothesis in a eusocial mammal: population genetics of the naked mole-rat, Heterocephalus glaber.

The role of genetic relatedness in the evolution of eusociality has been the topic of much debate, especially when contrasting eusocial insects with vertebrates displaying reproductive altruism. The naked mole-rat, Heterocephalus glaber, was the first described eusocial mammal. Although this discovery was based on an ecological constraints model of eusocial evolution, early genetic studies reported high levels of relatedness in naked mole-rats, providing a compelling argument that low dispersal rates and consanguineous mating (inbreeding as a mating system) are the driving forces for the evolution of this eusocial species. One caveat to accepting this long-held view is that the original genetic studies were based on limited sampling from the species’ geographic distribution. A growing body of evidence supports a contrary view, with the original samples not representative of the species—rather reflecting a single founder event, establishing a small population south of the Athi River. Our study is the first to address these competing hypotheses by examining patterns of molecular variation in colonies sampled from north and south of the Athi and Tana rivers, which based on our results, serve to isolate genetically distinct populations of naked mole-rats. Although colonies south of the Athi River share a single mtDNA haplotype and are fixed at most microsatellite loci, populations north of the Athi River are considerably more variable. Our findings support the position that the low variation observed in naked mole-rat populations south of the Athi River reflects a founder event, rather than a consequence of this species’ unusual mating system

DIYABCparameter

List of the parameters used in the DIYABC analyse

Ingram_etal_collecting_info

Additional information about the sample collection, including locality

Ingram_etal_partialMantelDloop

This is the input file used for the partial Mantel test- dloop on the Isolation by Distance Web Service http://ibdws.sdsu.edu/~ibdws

Ingram_etal_dloop_alignment

The nexus format alignment of dloop sequence of all the identified haplotypes. Redundent haplotypes were collapsed within locality. NCBI Accession numbers are included. Although Mtito Andei and Kathekani shared the exact same haplotype we included both sites to represent each locality

Heterocephalus glaber microsatellite genotype data

Genotypes for 131 individuals of Heterocephalus glaber using 12 H. glaber specific primers. Data is in Genepop format

Partial Mantel test - msat

This is the input datafile used on the Isolation by Distance Web Service http://ibdws.sdsu.edu/~ibdws

Monitoring health and reproductive status of olms (<i>Proteus anguinus</i>) by ultrasound

<div><p>The olm (<i>Proteus anguinus</i>) is a troglomorphic, neotenous amphibian with extraordinary life expectancy and unique adaptations that deserve further investigation. A low reproductive rate and habitat decline render it threatened by extinction. Establishing captive populations for maintenance and artificial breeding may one day become crucial to the species. Longitudinal, <i>in-vivo</i> assessment of inner organs is invaluable to our understanding of reproductive physiology, health, and behavior. Using ultrasound, we measured heart rate and assessed health and reproductive status of 13 captive olms at Zagreb Zoo. Heart rate averaged 42.9 ± 4.6 bpm (32–55 bpm), as determined via pulsed-wave Doppler at 4–12 MHz. By using frequencies of up to 70 MHz (ultrasound biomicroscopy), inner organs were visualized in detail. Assessment of the gastrointestinal tract provided insights into feeding status and digestive processes. Several subclinical pathologies were detected, including biliary sludge, subcutaneous edema, ascites, and skin lesions. Detection of skin lesions by ultrasound was more sensitive than visual adspection. Olms with ultrasonographically detected skin lesions tested positive for <i>Saprolegnia</i> and were treated. Three of the four affected individuals survived and subsequently tested negative for <i>Saprolegnia</i>. Sex was reliably determined; only one individual proved male. The reason for this extreme female-biased sex-ratio remains unknown. However, as most of the individuals were flushed from the caves by strong currents in spring, the sample may not be representative of natural populations. In female olms, different stages of ovarian follicular development were observed with diameters ranging between 0.1 and 1.1 mm. Results were confirmed by comparing ultrasound, necropsy, and histological findings of one dead specimen. In summary, ultrasound proved a valuable tool to support conservation and captive breeding programs by allowing non-invasive assessment of physiological parameters, clinical condition, and reproductive status in olms.</p></div