Citizen science has a long history in the ecological sciences and has made substantial contributions to science, education, and society. Developments in information technology during the last few decades have created new opportunities for citizen science to engage ever larger audiences of volunteers to help address some of ecology's most pressing issues, such as global environmental change. Using online tools, volunteers can find projects that match their interests and learn the skills and protocols required to develop questions, collect data, submit data, and help process and analyze data online. Citizen science has become increasingly important for its ability to engage large numbers of volunteers to generate observations at scales or resolutions unattainable by individual researchers. As a coupled natural and human approach, citizen science can also help researchers access local knowledge and implement conservation projects that might be impossible otherwise. In Japan, however, the value of citizen science to science and society is still underappreciated. Here we present case studies of citizen science in Japan, the United States, and the United Kingdom, and describe how citizen science is used to tackle key questions in ecology and conservation, including spatial and macro-ecology, management of threatened and invasive species, and monitoring of biodiversity. We also discuss the importance of data quality, volunteer recruitment, program evaluation, and the integration of science and human systems in citizen science projects. Finally, we outline some of the primary challenges facing citizen science and its future.

No abstract

IMPORTANCE Although mutations in 26 causative genes have been identified in the spinocerebellar ataxias (SCAs), the causative genes in a substantial number of families with SCA remain unidentified.OBJECTIVE To identify the causative gene of SCA in 2 Japanese families with distinct neurological symptoms and radiological presentations. DESIGN, SETTING, AND PARTICIPANTSClinical genetic study at a referral center of 11 members from 2 Japanese families, which started in 1997. MAIN OUTCOMES AND MEASURESResults of neurological examinations and radiological evaluations. The causative mutation was identified using genome-wide linkage analysis and next-generation sequencing.RESULTS Affected members (9 of 11 members [81.8%]) showed slowly progressive cerebellar ataxia (all 9 members [100%]), ocular movement disturbance (all 9 members [100%]), and pyramidal tract signs (8 of 9 members [88.9%]) with an age at onset between the second and sixth decades of life. Besides cerebellar and pontine atrophy, magnetic resonance imaging of the brain revealed the hot cross bun sign (4 of 6 members [66.7%]), pontine midline linear hyperintensity (2 of 6 members [33.3%]), or high intensity in the middle cerebellar peduncle (1 of 6 members [16.7%]), which are all reminiscent of multiple system atrophy in tested patients. Using linkage analysis combined with exome and whole-genome sequencing, we identified a novel heterozygous mutation in the ELOVL fatty acid elongase 4 (ELOVL4) gene (c.736T>G, p.W246G) in both families. Haplotype analysis indicated that it was unlikely that these 2 Japanese families shared a common ancestor. Although a missense mutation in ELOVL4 (c.504G>C, p.L168F) was recently reported to be associated with SCA with erythrokeratodermia variabilis (SCA34) in a French-Canadian family, signs of erythrokeratodermia variabilis were absent in our families. CONCLUSIONS AND RELEVANCECombined with the results of the family with SCA34 reported previously, this report confirms that mutations in ELOVL4 can cause dominantly inherited neurodegeneration severely affecting the cerebellum and brainstem. We should be aware that the presence of multiple system atrophy-like features on magnetic resonance imaging scans, together with cerebellar and brainstem atrophy, suggests SCA34, even when erythrokeratodermia variabilis is absent. The present study further broadened the spectrum of the clinical presentations of SCA34 associated with mutations in ELOVL4, which is involved in the biosynthesis of very long-chain fatty acids.

1 Fibril formation of amyloid b peptide (Ab) is considered to be responsible for the pathology of Alzheimer's disease (AD). The Ab ®bril is formed by a protein misfolding process in which intermolecular b-sheet interactions become stabilized abnormally. Thus, to develop potential anti-AD drugs, we screened an in-house library to ®nd compounds which have a pro®le as a b-sheet breaker.2 We searched for a b-sheet breaker pro®le in an in-house library of approximately 113,000 compounds. From among the screening hits, we focused on N,N'-bis(3-hydroxyphenyl)pyridazine-3,6-diamine (named RS-0406), which had been newly synthesized in our laboratory. This compound (10 ± 100 mg ml 71 ) was found to be capable of signi®cantly inhibiting 25 mM Ab 1 ± 42 ®brillogenesis and, furthermore, disassembling preformed Ab 1 ± 42 ®brils in vitro. 3 We then investigated the e ect of RS-0406 on 111 nM Ab 1 ± 42 -induced cytotoxicity in primary hippocampal neurons, and found that 0.3 ± 3 mg ml 71 RS-0406 ameliorates the cytotoxicity. Moreover, 3 mg ml 71 RS-0406 reversed 1 mM Ab 1 ± 42 -induced impairment of long-term potentiation in hippocampal slices. 4 In this study, we have succeeded in identifying RS-0406 which has potential to inhibit Ab 1 ± 42 ®brillogenesis, and to protect neurons against Ab 1 ± 42 -induced biological toxicity in vitro. These results suggest that RS-0406 or one of the derivatives could become a therapeutic agent for AD patients.

Migratory divides are proposed to be catalysts for speciation across a diversity of taxa. However, it is difficult to test the relative contributions of migratory behaviour vs. other divergent traits to reproductive isolation. Comparing hybrid zones with and without migratory divides offers a rare opportunity to directly examine the contribution of divergent migratory behaviour to reproductive barriers. We show that across replicate sampling transects of two pairs of barn swallow (Hirundo rustica) subspecies, strong reproductive isolation coincided with a migratory divide spanning 20 degrees of latitude. A third subspecies pair exhibited no evidence for a migratory divide and hybridised extensively. Within migratory divides, overwintering habitats were associated with assortative mating, implicating a central contribution of divergent migratory behaviour to reproductive barriers. The remarkable geographic coincidence between migratory divides and genetic breaks supports a long‐standing hypothesis that the Tibetan Plateau is a substantial barrier contributing to the diversity of Siberian avifauna.