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Aneuploidy typically poses challenges for cell survival and growth. However, recent studies have identified exceptions where aneuploidy is beneficial for cells with mutations in certain regulatory genes. Our research reveals that cells lacking the spindle checkpoint gene BUB3 exhibit aneuploidy of select chromosomes. While the spindle checkpoint is not essential in budding yeast, the loss of BUB3 and BUB1 increases the probability of chromosome missegregation compared to wildtype cells. Contrary to the prevailing assumption that the aneuploid cells would be outcompeted due to growth defects, our findings demonstrate that bub3 Δ cells consistently maintained aneuploidy of specific chromosomes over many generations. We investigated whether the persistence of these additional chromosomes in bub3 Δ cells resulted from the beneficial elevated expression of certain genes, or mere tolerance. We identified several genes involved in chromosome segregation and cell cycle regulation that confer an advantage to Bub3-depleted cells. Overall, our results suggest that the upregulation of specific genes through aneuploidy may provide a survival and growth advantage to strains with poor chromosome segregation fidelity. AUTHOR SUMMARY: Accurate chromosome segregation is crucial for the proper development of all living organisms. Errors in chromosome segregation can lead to aneuploidy, characterized by an abnormal number of chromosomes, which generally impairs cell survival and growth. However, under certain stress conditions, such as in various cancers, cells with specific mutations and extra copies of advantageous chromosomes exhibit improved survival and proliferation. In our study, we discovered that cells lacking the spindle checkpoint protein Bub3 became aneuploid, retaining specific chromosomes. This finding was unexpected because although bub3 Δ cells have a higher rate of chromosome mis-segregation, they were not thought to maintain an aneuploid karyotype. We investigated whether the increased copy number of specific genes on these acquired chromosomes offered a benefit to Bub3-deficient cells. Our results revealed that several genes involved in chromosome segregation and cell cycle regulation prevented the gain of chromosomes upon Bub3-depletion, suggesting that these genes confer a survival advantage. Overall, our study demonstrates that cells lacking Bub3 selectively retain specific chromosomes to increase the copy number of genes that promote proper chromosome segregation.

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PURPOSE: The purpose of this study was to provide Australian data on the clinical and radiological features and outcomes in patients with orbital plasmacytomas. METHODS: Multicentre retrospective review of orbital plasmacytoma and orbital involvement in multiple myeloma (MM) from 2005 to 2022 in Australia. RESULTS: Twenty-one participants were identified. The median age was 62 years (range 34-88 years), and 11 (52%) were females. Eighteen (84%) had a known diagnosis of MM prior to their orbital presentation, with all patients eventually being diagnosed with systemic MM. Thirteen (72%) were receiving active treatment for systemic myeloma on presentation, while 3 (17%) were in remission. All but 1 had unilateral orbital involvement (n = 20, 95%). Common presenting symptoms and signs were decreased visual acuity (n = 13, 62%), proptosis (n = 11, 52%), limited motility (n = 15, 71%), and optic neuropathy (n = 5, 24%). Radiologically, 15 (71%) involved the superotemporal orbit, 7 (33%) inferotemporal orbit, and 16 (76%) involved ≥1 extraocular muscle. Sixteen (76%) were biopsied and confirmed orbital plasmacytoma on histopathology. Treatment modalities included intravenous and oral steroids (n = 7, 33%), chemotherapy (n = 9, 43%), radiotherapy (n = 13, 62%), stem cell transplant (n = 3, 14%), and surgical debulking and decompression (n = 3, 14%). Mortality was high, with 15 (71%) having MM-related mortality. CONCLUSIONS: This is the largest cohort of Australian data on orbital plasmacytomas. Most patients have a diagnosis of systemic MM at presentation. It is crucial to recognize and treat these patients early due to a poor systemic prognosis.

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BACKGROUND: This study focuses on the efficacy and 2-year outcomes of ultra-low-dose radiotherapy (RT) in treating primary and secondary ocular adnexal lymphoma (OAL). METHODS: A retrospective analysis was conducted on patients with OAL between 2017 and 2022, treated with 4 Gy of RT. The primary and secondary outcomes assessed were response rate, progression-free survival, and lymphoma-related death. RESULTS: Twenty-one patients with primary and secondary OAL of diverse, presentations, subtypes, and stages were included. The orbital tumors had an average size of 17 × 16 × 16 mm. Of the 14 primary OAL cases, 3 (14%) had T1N0M0 disease, 8 (38%) T2N0M0, and 3 (14%) T3N0M0 (AJCC 8th edition staging); of the 7 secondary OALs, 4 (19%) were stage IE, 2 (10%) stage IIE, and 1 (5%) stage IIIE (Ann Arbor staging). Ultra-low-dose RT yielded a 95% complete response rate and 100% progression-free survival rates, both locally and systemically at 2 years. Mild dry eyes were reported in 14% of patients as a late treatment toxicity. CONCLUSIONS: Ultra-low-dose RT emerges as an effective and well-tolerated treatment approach for OAL. Our findings support the use of 4 Gy, showcasing high complete response rates (95%) and durable disease control without significant local relapses over an average follow up of 27 months. Our results align with earlier investigations, validating the curative potential of ultra-low-dose RT and reinforcing the concept of achieving favorable outcomes with minimal intervention. This approach may potentially alleviate the burden of long-term ocular side effects associated with higher radiation doses, enhancing the overall quality of life for OAL patients.

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The focus of this case study is the delayed diagnosis of a perinatal HIV transmission, which was identified when the infant reached 4 months of age, and the social conditions and structural determinants that contributed to the increased transmission risk. Despite adhering to the diagnostic testing protocols and neonatal antiretroviral (ARV) guidelines of the New York State Department of Health, this transmission still occurred. This transmission event prompted strategies to address criminalization of substance use during pregnancy and a reevaluation of the HIV testing and treatment protocols, including the timing of testing. Obtaining a diagnostic specimen at birth before initiating prophylactic or presumptive therapy, without causing delays in therapy, and incorporating HIV-1 DNA or RNA testing 2 to 6 weeks after discontinuing ARV therapy might have facilitated earlier detection and a quicker resumption of ARV therapy for this high-risk infant. Subsequently, the New York State HIV perinatal testing guidelines were updated. These changes included the recommendation to obtain a diagnostic specimen at birth before initiating ARV medications, whenever feasible, without causing delays in ARV initiation. Additionally, an extra virologic diagnostic test is recommended at 2 to 6 weeks after discontinuing ARVs for infants at high risk of perinatal HIV transmission, especially those with possible DNA or RNA suppression due to ARV prophylaxis or presumptive HIV therapy.

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Purpose: To evaluate percutaneous triamcinolone (TA) injection efficacy in treating upper eyelid retraction (UER) for Australian thyroid eye disease (TED) patients. Methods: We conducted a retrospective analysis across 8 years and multiple diverse Australian centres identified UER patients who received TA injections. A single operator administered 40mg/1ml TA through upper eyelid skin. Assessments at 4-6 weeks and subsequent eyelid measurements gauged treatment response and complications. Results: 24 patients and 25 eyelids were included in the study. 91.6% were female, mean age 40.8 ± 10.3 years with mean follow-up of 17.5 months (± 18.5). Pre-treatment MRD1 was 6.2mm ± 1.4, and we observed a mean improvement of 2.2mm from pre-treatment to post-treatment (p<0.001). The mean UER measurement before treatment (defined as MRD1 - 4.0mm) was 3.0mm ± 1.3 (range, 0-6mm). After treatment, the mean UER measurement was -0.1mm. Quality of life (QOL) assessment improved significantly, from pre-treatment score of 4.13 ± 2.4 to post-treatment 8.0 ±1.7 (p<0.001). Conclusions: Percutaneous injection of TA is an effective and safe treatment option for UER in patients with TED. This technique can be performed without upper eyelid eversion, which makes it more tolerable for patients and less complex for the operator compared to the transconjunctival injection approach. Our results show a significant improvement in MRD1 and UER, as well as patient QOL. Moreover, we found a low rate of complications (4.2% induced ptosis) and no cases of raised intraocular pressure. Percutaneous TA injection can greatly reduce the need for eyelid lowering surgery in this patient population.

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PURPOSE: To evaluate the disease characteristics and survival of patients with ocular adnexal T-cell lymphoma. METHODS: A retrospective, observational study of patients with a histopathological diagnosis of T-cell lymphoma of the ocular adnexa seen between 1992 and 2022. Demographic data, clinical presentation, imaging, histology, immunohistochemistry, treatment, and outcomes were reviewed. RESULTS: Fifteen patients were included in the study with the mean age at diagnosis of 50 years old (range 7-85). The most common presenting symptoms were ulcerated eyelid skin lesions (40%) followed by eyelid swelling (13.3%), and lacrimal passageways obstruction (13.3%). The anaplastic large cell lymphoma (33%) and primary cutaneous T-cell lymphoma (33%) were the most diagnosed peripheral T-cell lymphoma subtypes, followed by the nasal type natural killer/T-cell lymphoma (27%) and peripheral T-cell lymphoma not otherwise specified (7%). The most prevalent stage of disease progression was stage I and stage IV (Ann Arbor classification) with seven (47%) patients each. Eight (53%) patients succumbed to the disease process of which three (37.5%) deceased in the first six months and six (75%) within the first year of diagnosis. We identified a strong statistical association between stage and disease-related death ( p = 0.003). CONCLUSIONS: Peripheral T-cell lymphoma occurring in the orbit and ocular adnexa is extremely rare. Advanced stage at diagnosis leads to almost certain death from the disease despite aggressive local and systemic treatment. Early diagnosis improves the chances of survival but can be hindered by this condition's ability to simulate benign inflammatory conditions both clinically and histologically.

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We describe the first reported case of granulomatosis polyangiitis (GPA)-associated sclerokeratitis in a patient with treated ocular adnexal lymphoma (OAL). The patient presented with pain and decreased vision in the left eye over several weeks. Past medical history was significant for recent bilateral relapsing OAL that was treated successfully with radiotherapy. Examination of the eyes revealed sectoral scleritis and peripheral ulcerative keratitis. Magnetic resonance imaging (MRI) of the orbits excluded recurrence of OAL and serum antineutrophil cytoplasmic autoantibody (ANCA) titres confirmed the diagnosis of GPA. Disease was poorly responsive to systemic steroids, azathioprine and rituximab. Ultimately, resolution was achieved with successive subconjunctival dexamethasone and subconjunctival triamcinolone injections. This case highlights the need to consider ocular inflammation in patients with a history of malignant hemopathies.

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We present the long-term follow-up of a case of periorbital congenital infantile fibrosarcoma (CIFS) treated with chemotherapy and surgery. The tumor was detected on a routine prenatal ultrasound at 30 weeks of gestation and diagnosed via an orbital biopsy day 9 postnatal age. The patient underwent chemotherapy and surgical debulking within the first 3 months of life and has maintained complete tumor remission for 7 years. The case highlights that early recognition and prompt treatment of periorbital CIFS can lead to complete long-term remission of this uncommon malignancy.

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Critical loads (CLs) and target loads (TLs) of atmospheric deposition of sulfur (S) and nitrogen (N) specify the thresholds of air pollution above which damage to ecosystems is expected to occur and are used to inform environmental regulation and natural resource management. Model estimates of CL and TL can vary for a given location, and these differences can be important for characterization of ecosystem effects from elevated S and N deposition. Moreover, TLs are used to evaluate associated timeframes of ecosystem recovery. We compared published CLs and TLs based on soil acidity criteria derived from steady-state versus dynamic models for terrestrial ecosystems. We examined the magnitude of differences in the CL/TL results from the two types of models for the same regions in the Eastern U.S. Results showed that CLs/TLs from dynamic models (or from steady state modeling using soil base cation weathering estimates from dynamic models) generally produce a broader range of values of acid-sensitivity, including lower CLs/TLs, as compared with a steady-state approach. Applications of dynamic biogeochemical models capable of developing CLs/TLs are relatively data intensive and typically limited to locations where measured soil and soil solution (or nearby stream water) chemistry are available for model parameterization, calibration, and testing. We recommend that CLs/TLs derived from dynamic models be used, where data permit, as they are likely more accurate and allow for evaluation of time-dependent phenomena and period needed for recovery. However, CLs derived from steady-state models remain a useful tool for understanding broad spatial patterns in soil acid-sensitivity throughout the U.S. Future work should focus on the development of more reliable model input parameters, particularly soil base cation weathering, and the extent to which CLs and TLs at a given location may vary and be altered with anticipated future climate change. In addition, dynamic models could be further developed to estimate CLs/TLs for nutrient N.

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A 92-year-old man presented with progressively worsening eye pain, diplopia on lateral gaze and blurred vision for the past 12 months. Radiological imaging confirmed a large left lacrimal gland lesion. The patient subsequently underwent a superio-lateral orbitotomy with left dacryoadenectomy and tumor removal, histopathology subsequently confirmed an epithelial-myoepithelial carcinoma arising ex pleomorphic adenoma of the lacrimal gland. Epithelial-myoepithelial carcinoma is a rare lacrimal gland tumour and the authors believe this case to be the first reported in the Australian population and associated with prolonged eye pain.

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Atlantic cod (Gadus morhua, Linnaeus 1758) in the western Gulf of Maine are managed as a single stock despite several lines of evidence supporting two spawning groups (spring and winter) that overlap spatially, while exhibiting seasonal spawning isolation. Low-coverage whole-genome sequencing was used to evaluate the genomic population structure of Atlantic cod spawning groups in the western Gulf of Maine and Georges Bank using 222 individuals collected over multiple years. Results indicated low total genomic differentiation, while also showing strong differentiation between spring and winter-spawning groups at specific regions of the genome. Guided regularized random forest and ranked F ST methods were used to select panels of single nucleotide polymorphisms (SNPs) that could reliably distinguish spring and winter-spawning Atlantic cod (88.5% assignment rate), as well as males and females (95.0% assignment rate) collected in the western Gulf of Maine. These SNP panels represent a valuable tool for fisheries research and management of Atlantic cod in the western Gulf of Maine that will aid investigations of stock production and support accuracy of future assessments.

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Social scientists have long utilized observations of human behavior in research designs. For researchers studying couples, observation of romantic partners has led to important discoveries about how such behavior is associated with physical, mental, and family health. Historically, these methods have been used in in-person laboratory paradigms that place notable limitations on reach and inclusion. This has, in turn, restricted the generalizability of such research to couples who may not attend an in-person laboratory assessment. Transferring the observational laboratory into an online format has the potential to expand the capabilities of these methods to include more diverse couples. This article presents two empirical studies that used online methods to conduct observational behavioral research with sexual and gender minority couples, populations that could be difficult to reach using traditional methods in many places. We demonstrate that we were able to reach, recruit, and enroll diverse couples that more closely resemble the population of same-sex couples in the United States than likely would have been reached in-person. Further, we show that the quality of the observational data collected via the internet allowed for over 94% of collected data to be coded, with acceptable interrater reliabilities and convergent validity. These studies provide a proof-of-concept of online observational methods, accompanied by a tutorial for using such methods. We discuss possible extensions of these online methods, their limitations, and the potential to help further the field of close relationships by reaching more diverse relationships and increasing the generalizability of our research. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

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Bacteriophages exert strong evolutionary pressure on their microbial hosts. In their lytic lifecycle, complete bacterial subpopulations are utilized as hosts for bacteriophage replication. However, during their lysogenic lifecycle, bacteriophages can integrate into the host chromosome and alter the host's genomic make-up, possibly resulting in evolutionary important adjustments. Not surprisingly, bacteria have evolved sophisticated immune systems to protect against phage infection. Streptococcus pyogenes isolates are frequently lysogenic and their prophages have been shown to be major contributors to the virulence of this pathogen. Most S. pyogenes phage research has focused on genomic prophages in relation to virulence, but little is known about the defensive arsenal of S. pyogenes against lytic phage infection. Here, we characterized Phage A1, an S. pyogenes bacteriophage, and investigated several mechanisms that S. pyogenes utilizes to protect itself against phage predation. We show that Phage A1 belongs to the Siphoviridae family and contains a circular double-stranded DNA genome that follows a modular organization described for other streptococcal phages. After infection, the Phage A1 genome can be detected in isolated S. pyogenes survivor strains, which enables the survival of the bacterial host and Phage A1 resistance. Furthermore, we demonstrate that the type II-A CRISPR-Cas system of S. pyogenes acquires new spacers upon phage infection, which are increasingly detectable in the absence of a capsule. Lastly, we show that S. pyogenes produces membrane vesicles that bind to phages, thereby limiting the pool of phages available for infection. Altogether, this work provides novel insight into survival strategies employed by S. pyogenes to combat phage predation.

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BACKGROUND: Coronavirus disease 2019 (COVID-19) convalescent plasma (CCP) received an Emergency Use Authorization by the US Food and Drug Administration (FDA). CCP with a signal-to-cutoff ratio of ≥12 using the Ortho VITROS severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immunoglobulin G (IgG) test (OVSARS2IgG) is permitted to be labeled "high titer." Little is known about the relationship between OVSARS2IgG ratio and neutralizing capacity of plasma/sera against genuine SARS-CoV-2. METHODS: Nine hundred eighty-one samples from 196 repeat CCP donors 0-119 days post-initial donation (DPID) were analyzed. Neutralizing capacity was assessed for 50% (PRNT50) and 90% (PRNT90) reduction of infectious virus using the gold standard plaque reduction neutralization test (PRNT). A subset of 91 donations was evaluated by OVSARS2IgG and compared to PRNT titers for diagnostic accuracy. RESULTS: Of donations, 32.7%/79.5% (PRNT90/PRNT50) met a 1:80 titer initially but only 14.0%/48.8% (PRNT90/PRNT50) met this cutoff ≥85 DPID. Correlation of OVSARS2IgG results to neutralizing capacity allowed extrapolation to CCP therapy results. CCP with OVSARS2IgG ratios equivalent to a therapeutically beneficial group had neutralizing titers of ≥1:640 (PRNT50) and/or ≥1:80 (PRNT90). Specificity and positive predictive value of the OVSARS2IgG for qualifying highly neutralizing CCP was optimal using ratios significantly greater than the FDA cutoff. CONCLUSIONS: This information provides a basis for refining the recommended properties of CCP used to treat COVID-19.

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PURPOSE: To evaluate the clinical features, management, and outcomes of orbital schwannomas. METHODS: Retrospective study analyzing 20 orbital schwannomas in 18 patients managed in an orbital service over 26 years. Clinical, radiological, histological, and surgical procedural data were analyzed. RESULTS: Mean age of the study population was 40.89 ± 20.84 years. The most common nerve of origin was frontal nerve (50%), and majority of patients (70%) had a superior and/or posteriorly located tumor. Five patients (27.8%) had optic neuropathy at presentation, and 3 of them showed improved vision after intervention. Surgical resection was performed for all except for 1 patient who underwent fractionated stereotactic radiotherapy. Six subjects had extension of tumor into the cavernous sinus, and 3 of them underwent combined neurosurgical intervention with stereotactic neuronavigation. Outcomes were largely favorable with majority achieving complete excision. Two out of 6 incomplete resections experienced regrowth requiring second surgical intervention. Surgical complications include decreased vision, diplopia, ptosis, and mydriasis. CONCLUSION: Orbital schwannomas are uncommon slow-growing tumors which can result in visual loss. Prognosis can be favorable even in presence of pre-operative optic neuropathy if there is early intervention. Schwannomas confined to the orbit can usually be completely excised with good outcomes. Schwannomas extending intra-cranially may undergo incomplete excision to preserve vital structures, leaving residual disease, but generally have satisfactory results. Stereotactic neuronavigation and frozen section are useful intra-operative tool to aid management and minimize complications. Fractionated radiotherapy can be considered as an alternative or adjunctive treatment for patients not amenable for surgical resections.

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The RNA-programmable DNA-endonuclease Cas9 is widely used for genome engineering, where a high degree of specificity is required. To investigate which features of Cas9 determine the sensitivity to mismatches along the target DNA, we performed in vitro biochemical assays and bacterial survival assays in Escherichia coli. We demonstrate that arginines in the Cas9 bridge helix influence guide RNA, and target DNA binding and cleavage. They cluster in two groups that either increase or decrease the Cas9 sensitivity to mismatches. We show that the bridge helix is essential for R-loop formation and that R63 and R66 reduce Cas9 specificity by stabilizing the R-loop in the presence of mismatches. Additionally, we identify Q768 that reduces sensitivity of Cas9 to protospacer adjacent motif-distal mismatches. The Cas9_R63A/Q768A variant showed increased specificity in human cells. Our results provide a firm basis for function- and structure-guided mutagenesis to increase Cas9 specificity for genome engineering.

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The present-day acid-base chemistry of surface waters can be directly linked to contemporary observations of acid deposition; however, pre-industrial conditions are key to predicting the potential future recovery of stream ecosystems under decreasing loads of atmospheric sulfur (S) and nitrogen (N) deposition. The integrated biogeochemical model PnET-BGC was applied to 25 forest watersheds that represent a range of acid sensitivity in the Adirondack region of New York, USA to simulate the response of streams to past and future changes in atmospheric S and N deposition, and calculate the target loads of acidity for protecting and restoring stream water quality and ecosystem health. Using measured data, the model was calibrated and applied to simulate soil and stream chemistry at all study sites. Model hindcasts indicate that historically stream water chemistry in the Adirondacks was variable, but inherently sensitive to acid deposition. The median model-simulated acid neutralizing capacity (ANC) of the streams was projected to be 55 µeq L-1 before the advent of anthropogenic acid deposition (~1850), decreasing to minimum values of 10 µeq L-1 around the year 2000. The median simulated ANC increased to 13 µeq L-1 by 2015 in response to decreases in acid deposition that have occurred over recent decades. Model projections suggest that simultaneous decreases in sulfate, nitrate and ammonium deposition are more effective in restoring stream ANC than individual decreases in sulfur or nitrogen deposition. However, the increases in stream ANC per unit equivalent decrease in S deposition is greater compared to decreases in N deposition. Using empirical algorithms, fish community density and biomass are projected to increase under several deposition-control scenarios that coincide with increases in stream ANC. Model projections suggest that even under the most aggressive deposition-reduction scenarios, stream chemistry and fisheries will not fully recover from historical acidification by 2200.

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Primitive myxoid mesenchymal tumor of infancy is a rare subtype of sarcoma. With the advent of relevant immunohistochemical and genetic analysis, it was defined by Alaggio et al. in a 2006 case series. Since then, 25 further cases are described in the literature-arising variably from the neck, chest, scalp, abdomen, back, or limbs. Here it is described for the first time arising in the orbit, confirmed by identification of BCOR immunopositivity with internal tandem duplication. All specialties involved in the management of orbital masses should be aware of the subtypes of sarcomas found in the orbit as approaches to their management may change depending on the diagnosis. As more cases are identified, a better understanding of this tumor's clinical behavior and appropriate management can be established.

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Species susceptible to inbreeding depression are hypothesized to combat this problem through a number of different mechanisms, including kin recognition. For species with kin recognition, it is unknown if filial recognition is innate or due to prior juvenile experience with siblings. Here, we first test for the presence of kin recognition, and then test these two hypotheses for the development of filial recognition, in the butterfly Bicyclus anynana, a species that suffers from inbreeding depression when forcibly inbred but recovers within a few generations when allowed to breed freely. We evaluate whether the rapid recovery from inbreeding depression is associated with either innate or learned filial recognition. First, we determined whether females innately prefer unrelated males over sibling males using females reared in isolation and then given a choice between an unrelated and a sibling male. Then, we determined if females raised with siblings learned to detect and avoid mating with siblings as adults when provided a choice between an unrelated male and a sibling male. Finally, we determined if females raised with siblings could learn to detect and avoid mating with familiar siblings when given a choice between familiar and unfamiliar siblings. We found that females mated randomly in all three choice combinations. Observed male behavior also did not influence female mating outcome. Our results suggest that adult females do not innately avoid or learn to avoid siblings during mate selection, and that filial detection may not be as critical to reproductive fitness in B. anynana as previously thought.

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