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Schärer Group
Evolutionary Biology
Zoological Institute
University of Basel
Vesalgasse 1
CH-4051 Basel

Publications (for entries with an asterisk (*) see bottom of page for corrections and additions)

80. Brand, J. N., Harmon, L. J. & Schärer, L. (2022). Mating behavior and reproductive morphology predict macroevolution of sex allocation in hermaphroditic flatworms. BMC Biology 20: 35 (pdf)

79. Brand, J. N., Harmon, L. J. & Schärer, L. (2022). Frequent origins of traumatic insemination involve convergent shifts in sperm and genital morphology. Evolution Letters 6: 63-82 (pdf)

78. Brand, J. N., Viktorin, G., Wiberg, R. A. W., Beisel, C. & Schärer, L. (2022). Large-scale phylogenomics of the genus Macrostomum (Platyhelminthes) reveals cryptic diversity and novel sexual traits. Molecular Phylogenetics and Evolution 166: 107296 (pdf)

77. Wiberg, R. A. W., Brand, J. N. & Schärer, L. (2021). Faster rates of molecular sequence evolution in reproduction-related genes and in species with hypodermic sperm morphologies. Molecular Biology and Evolution 31(12): 5685–5703 (pdf)

76. Smith, J. P. S., III, & Schärer, L. (2021). Bradynectes ensifer n. sp. (Platyhelminthes: Macrostomorpha) from North Carolina, USA. Zootaxa 4927: 587-592 (pdf)

75. Marie-Orleach, L., Vellnow, N. & Schärer, L. (2021). The repeatable opportunity for selection differs between pre- and postcopulatory fitness components. Evolution Letters 5: 101-114 (pdf)

74. Singh, P., Ballmer, D. N., Laubscher, M. & Schärer, L. (2020). Successful mating and hybridisation in two closely related flatworm species despite significant differences in reproductive morphology and behaviour. Scientific Reports 10: 12830 (pdf)

73. Brand, J. N., Wiberg, R. A. W., Pjeta, R., Bertemes, P., Beisel, C., Ladurner, P. & Schärer, L. (2020). RNA-Seq of three free-living flatworm species suggests rapid evolution of reproduction-related genes. BMC Genomics 21: 462 (pdf)

72. Kaufmann, P. & Schärer, L. (2020). Is the initiation of selfing linked to a hermaphrodite's female or male reproductive function? Behavioral Ecology and Sociobiology 74: 41 (pdf)

71. Wudarski, J., Egger, B., Ramm, S. A., Schärer, L., Ladurner, P., Zadesenets, K. S., Rubtsov, N. B., Mouton, S. & Berezikov, E. (2020). The free-living flatworm Macrostomum lignano. EvoDevo 11: 5 (pdf)

70. Zadesenets, K. S., Jetybayev, I. Y., Schärer, L. & Rubtsov, N. B. (2020). Genome and karyotype reorganization after whole genome duplication in free-living flatworms of the genus Macrostomum. International Journal of Molecular Sciences 21: 680 (pdf)

69. Schärer, L., Brand, J. N., Singh, P., Zadesenets, K. S., Stelzer, C.-P. & Viktorin, G. (2020). A phylogenetically informed search for an alternative Macrostomum model species, with notes on taxonomy, mating behavior, karyology, and genome size. Journal of Zoological Systematics and Evolutionary Research 58: 41-65 (pdf of 2020 print version) (pdf of 2019 electronic version relevant for naming)

68. Singh, P., Vellnow, N. & Schärer, L. (2020). Variation in sex allocation plasticity in three closely related flatworm species. Ecology and Evolution 10: 26-37 (pdf)

67. Ramm, S. A., Lengerer, B., Arbore, R., Pjeta, R., Wunderer, J., Giannakara, A., Berezikov, E., Ladurner, P. & Schärer, L. (2019). Sex allocation plasticity on a transcriptome scale: socially sensitive gene expression in a simultaneous hermaphrodite. Molecular Ecology 28: 2321-2341 (pdf)

66. Weber, M., Wunderer, J., Lengerer, B., Pjeta, R., Rodrigues, M., Schärer, L., Ladurner, P. & Ramm, S. A. (2018). A targeted in situ hybridization screen identifies putative seminal fluid proteins in a simultaneously hermaphroditic flatworm. BMC Evolutionary Biology 18: 81 (pdf)

65. Vellnow, N., Marie-Orleach, L., Zadesenets, K. & Schärer, L. (2018). Bigger testes increase paternity in a simultaneous hermaphrodite, independently of the sperm competition level. Journal of Evolutionary Biology 31: 180-196 (pdf)

64. Schärer, L. (2017). Wieso sind Spermien so divers? Pp. 172 in Füglister KM, Hicklin M & Mäser P, eds. Natura Obscura. Schwabe Verlag, Basel, Switzerland. (pdf) (link)

63. Wudarski, J., Simanov, D., Ustyantsev, K., de Mulder, K., Grelling, M., Grudniewska, M., Beltman, F., Glazenburg, L., Demircan, T., Wunderer, J., Qi, W., Vizoso, D. B., Weissert, P. M., Olivieri, D., Mouton, S., Guryev, V., Aboobaker, A., Schärer, L., Ladurner, P. & Berezikov, E. (2017). Efficient transgenesis and annotated genome sequence of the regenerative flatworm model Macrostomum lignano. Nature Communications 8: 2120 (pdf) (suppl)

62. Zadesenets, K., Schärer, L. & Rubtsov, N. B. (2017). New insights into the karyotype evolution of the free-living flatworm Macrostomum lignano (Platyhelminthes, Turbellaria). Scientific Reports 7: 6066 (pdf)

61. Vellnow, N., Vizoso, D. B., Viktorin, G. & Schärer, L. (2017). No evidence for strong cytonuclear conflict over sex allocation in a simultaneously hermaphroditic flatworm. BMC Evolutionary Biology 17: 103 (pdf)

60. Marie-Orleach, L., Vogt-Burri, N., Mouginot, P., Schlatter, A., Vizoso, D. B., Bailey, N. W. & Schärer, L. (2017). Indirect genetic effects and sexual conflicts: partner genotype influences multiple morphological and behavioural reproductive traits in a flatworm. Evolution 71: 1232–1245 (pdf)

59. Schärer, L. (2017). The varied ways of being male and female. Molecular Reproduction and Development 84: 94-104 (pdf) (an introductory article to a special issue on hermaphrodites)

*58. Zadesenets, K., Vizoso, D. B., Schlatter, A., Konopatskaia, I. D., Berezikov, E., Schärer, L. & Rubtsov, N. B. (2016). Evidence for karyotype polymorphism in the free-living flatworm, Macrostomum lignano, a model organism for evolutionary and developmental biology. PLOS ONE 11: e0164915 (pdf)

*57. Janicke, T., Sandner, P., Ramm, S. A., Vizoso, D. B. & Schärer, L. (2016). Experimentally evolved and phenotypically plastic responses to enforced monogamy in a hermaphroditic flatworm. Journal of Evolutionary Biology 29: 1713-1727 (pdf)

56. Lehtonen, J., Parker, G. A. & Schärer, L. (2016). Why anisogamy drives ancestral sex roles. Evolution 70: 1129-1135 (pdf)(supplement)

55. Giannakara, A., Schärer, L. & Ramm, S. R. (2016). Sperm competition-induced plasticity in the speed of spermatogenesis. BMC Evolutionary Biology 16:60 (pdf)

54. Marie-Orleach, L., Janicke, T., Vizoso, D. B., David, P. & Schärer, L. (2016). Quantifying episodes of sexual selection: insights from a transparent worm with fluorescent sperm. Evolution 70: 314-328 (pdf)

53. Schärer, L. & Ramm, S. A. (2016). Hermaphrodites. In: Kliman, R. (ed.). Encyclopedia of Evolutionary Biology. Elsevier. Vol. 2. pp. 212-224 (pdf)

52. Wasik, K. A., Gurtowski, J., Zhou, X., Mendivil Ramos, O., Delás, M. J., Battistoni, G., El Demerdash, O., Falciatori, I., Vizoso, D. B., Smith, A. D., Ladurner, P., Schärer, L., McCombie, W. R., Hannon, G. J., Schatz, M. C. 2015. Genome and transcriptome of the regeneration-competent flatworm, Macrostomum lignano. Proceedings of the National Academy of Sciences of the USA 112: 12462-12467 (pdf) (link) (press release)

*51. Janssen, T., Vizoso, D. B., Schulte, G., Littlewood, D. T. J., Waeschenbach, A. & Schärer, L. (2015). The first multi-gene phylogeny of the Macrostomorpha sheds light on the evolution of sexual and asexual reproduction in basal Platyhelminthes. Molecular Phylogenetics and Evolution 92: 82-107 (pdf) (Table A) (Table B) (Table C corrected)

50. Ramm, S. A., Schlatter, A., Poirier, M. & Schärer, L. (2015). Hypodermic self-insemination as a reproductive assurance strategy. Proceedings of the Royal Society of London Series B 282: 20150660 (pdf) (press release) (press coverage)

49. Arbore, R., Sekii, K., Beisel, C., Ladurner, P., Berezikov, E. & Schärer, L. (2015). Positional RNA-Seq identifies candidate genes for phenotypic engineering of sexual traits in Macrostomum lignano. Frontiers in Zoology 12: 14 (pdf)

48. Ramm, S. A., Schärer, L., Ehmcke, J. & Wistuba, J. (2014). Sperm competition and the evolution of spermatogenesis. Molecular Human Reproduction 20: 1169-1179 (pdf)

47. Marie-Orleach, L., Janicke, T., Vizoso, D. B., Eichmann, M. & Schärer, L. (2014). Fluorescent sperm in a transparent worm: validation of a GFP marker to study sexual selection. BMC Evolutionary Biology 14: 148 (pdf) (highlighted in Editors's pick)

46. Schärer, L., Janicke, T. & Ramm, S. A. (2014). Sexual conflict in hermaphrodites. Cold Spring Harbor Perspectives in Biology. doi: 10.1101/cshperspect.a017673 (pdf) (1 of 23 chapters in Rice, W. R. & Gavrilets, S., eds.). The Genetics and Biology of Sexual Conflict. Cold Spring Harbor Press)

45. Ellis, R. E. & Schärer, L. (2014). Rogue sperm indicate sexually antagonistic co-evolution in nematodes. PLoS Biology 12: e1001916 (pdf) (a Primer on a paper by Ting et al. 2014)

44. Schärer, L. (2014). Evolution: Don't Be So Butch, Dear! Current Biology 24: R311-R313 (pdf) (a Dispatch on a paper by Nakadera et al. 2014)

43. Lengerer, B., Pjeta, R., Wunderer, J., Rodrigues, M., Arbore, R., Schärer, L., Berezikov, E., Hess, M., Pfaller, K., Egger, B., Obwegeser, S., Salvenmoser, W., and Ladurner, P. (2014). Biological adhesion of the flatworm Macrostomum lignano relies on a duo-gland system and is mediated by a cell type-specific intermediate filament protein. Frontiers in Zoology 11: 12 (pdf)

42. Ramm, S. A. & Schärer, L. (2014). The evolutionary ecology of testicular function: size isn’t everything. Biological Reviews 89: 874-888 (pdf)

41. Janicke, T., Marie-Orleach, L., De Mulder, K., Berezikov, E., Ladurner, P., Vizoso, D. B, & Schärer, L. (2013). Sex allocation adjustment to mating group size in a simultaneous hermaphrodite. Evolution 67: 3233–3242 (pdf)

40. Sekii, K., Vizoso, D. B., Kuales, G., De Mulder, K., Ladurner, P. & Schärer, L. (2013). Phenotypic engineering of sperm-production rate confirms evolutionary predictions of sperm competition theory. Proceedings of the Royal Society of London Series B 280: 20122711 (pdf)

39. Marie-Orleach, L., Janicke, T. & Schärer, L. (2013). Effects of mating status on copulatory and post-copulatory behaviour in a simultaneous hermaphrodite. Animal Behaviour 85: 453-461 (pdf)

38. Schärer, L. & Pen, I. (2013). Sex allocation and investment into pre- and postcopulatory traits in simultaneous hermaphrodites: the role of polyandry and local sperm competition. Philosophical Transactions of the Royal Society of London Series B 368: 20120052 (pdf)

37. Ramm, S. A., Vizoso, D. B. & Schärer, L. (2012). Occurrence, costs and heritability of delayed selfing in a free-living flatworm. Journal of Evolutionary Biology 25: 2559-2568 (pdf)

36. Schärer, L., Rowe, L. & Arnqvist, G. (2012). Anisogamy, chance and the evolution of sex roles.Trends in Ecology and Evolution 27: 260-264 (pdf)

35. Janicke, T., Kesselring, H. & Schärer, L. (2012). Strategic mating effort in a simultaneous hermaphrodite: the role of the partner's feeding status. Behavioral Ecology and Sociobiology 66:593-601 (pdf)

*34. Schärer, L., Littlewood, D. T. J., Waeschenbach, A., Yoshida, W. & Vizoso, D. B. (2011). Mating behaviour and the evolution of sperm design. Proceedings of the National Academy of Sciences of the USA 108:1490-1495 (pdf) (press release) (press coverage) (images and videos for the press)

33. Janicke, T., Sandner, P. & Schärer, L. (2011). Determinants of female fecundity in a simultaneous hermaphrodite: the role of polyandry and food availability. Evolutionary Ecolology 25: 203-218 (pdf)

32. Anthes, N., David, P., Auld, J. R., Hoffer, J. N. A., Jarne, P., Koene, J. M., Kokko, H., Lorenzi, M. C., Pelissié, B., Sprenger, D., Staikou, A. & Schärer, L. (2010). Bateman gradients in hermaphrodites: An extended approach to quantify sexual selection. American Naturalist 276: 249-263 (pdf)

31. Janicke, T. & Schärer, L. (2010). Sperm competition affects sex allocation but not sperm morphology in a flatworm. Behavioral Ecology and Sociobiology 64: 1367-1375 (pdf)

30. Sandner, P. & Schärer, L. (2010). No plastic responses to experimental manipulation of sperm competition in a free-living flatworm. Ethology 116: 292-299 (pdf).

*29. Vizoso, D. B., Rieger, G. & Schärer, L. (2010). Goings-on inside a worm: functional hypotheses derived from sexual conflict thinking. Biological Journal of the Linnean Society 99:370-383 (pdf).

28. Sekii, K., Salvenmoser, W., De Mulder, K., Schärer, L. & Ladurner, P. (2009). Melav2, an elav-like gene involved in spermatid differentiation in the flatworm Macrostomum lignano. BMC Developmental Biology 9:62 (pdf)

27. Janicke, T. & Schärer, L. (2009b). Sex allocation predicts mating rate in a simultaneous hermaphrodite. Proceedings of the Royal Society of London Series B 276: 4247-4253 (pdf)

26. Van Velzen, E., Schärer, L. & Pen, I. (2009). The effect of cryptic female choice on sex allocation in simultaneous hermaphrodites. Proceedings of the Royal Society of London Series B 276: 3123-3131 (pdf)

25. Schärer, L. (2009). Tests of sex allocation theory in simultaneously hermaphroditic animals. Evolution 63: 1377-1405 (pdf)

24. Schärer, L. & Janicke T. (2009). Sex allocation and sexual conflict in simultaneously hermaphroditic animals. Biology Letters 5: 705-708 (pdf) (entire special issue)

*23. Janicke, T. & Schärer, L. (2009a). Determinants of mating and sperm-transfer success in a simultaneous hermaphrodite. Journal of Evolutionary Biology 22: 405-415 (pdf)

22. Mouton, S., Willems, M., Braeckman, B. P., Egger, B., Ladurner, P., Schärer, L. & Borgonie, G. (2009). The free-living flatworm Macrostomum lignano: a new model organism for ageing research. Experimental Gerontology 44: 243-249 (pdf)

21. Ladurner, P., Egger, B., De Mulder, K., Pfister, D., Kuales, G., Salvenmoser, W. & Schärer, L. (2008). The stem cell system of the basal flatworm Macrostomum lignano. In Bosch, T. C. G. (ed.). Stem Cells: from Hydra to Man. Springer, Berlin (pdf)

20. Schärer, L., Da Lage, J.-L. & Joly, D. (2008). Evolution of testicular architecture in the Drosophilidae: a role for sperm length. BMC Evolutionary Biology 8: 143 (pdf)

19. Schärer, L., Vizoso, D. B., Rieger, G. & Peintner, U. (2007). Thraustochytrids as novel parasitic protists of marine free-living flatworms: Thraustochytrium caudivorum sp. nov. parasitizes Macrostomum lignano. Marine Biology 152: 1095–1104 (pdf)

18. Vizoso, D. B. & Schärer, L. (2007). Resource-dependent sex allocation in a simultaneous hermaphrodite. Journal of Evolutionary Biology 20: 1046-1055 (pdf)

17. Brauer, V., Schärer, L. & Michiels, N. K. (2007). Phenotypically flexible sex allocation in a simultaneous hermaphrodite. Evolution 61: 216-222 (pdf)

*16. Schärer, L., Zaubzer, J., Salvenmoser, W., Seifarth, C. & Ladurner, P. (2007). Tracking sperm of a donor in a recipient: an immunocytochemical approach. Animal Biology 57: 121-136 (pdf)

15. Schärer, L. & Vizoso, D. B. (2007). Phenotypic plasticity in sperm production rate: there's more to it than testis size. Evolutionary Ecology 21: 295-306 (pdf)

*14. Ladurner, P., Schärer, L., Salvenmoser, W. & Rieger, R. M. (2005). A new model organism among the lower Bilateria and the use of digital microscopy in taxonomy of meiobenthic Platyhelminthes: Macrostomum lignano, n. sp. (Rhabditophora, Macrostomorpha). Journal of Zoological Systematics and Evolutionary Research 43: 114-126 (pdf)

*13. Ladurner, P., Pfister, D., Seifarth, C., Schärer, L., Mahlknecht, M., Salvenmoser, W., Gerth, R. & Rieger, R. (2005). Production of cell- and tissue-specific monoclonal antibodies for the flatworm Macrostomum sp. Histochemistry and Cell Biology 123: 89-104 (pdf)

*12. Schärer, L., Sandner, P. and Michiels, N. K. (2005). Trade-off between male and female allocation in the simultaneously hermaphroditic flatworm Macrostomum sp. Journal of Evolutionary Biology 18: 396-404 (pdf)

*11. Schärer, L., Ladurner, P. & Rieger, R. M. (2004). Bigger testes do work more: experimental evidence that testis size reflects testicular cell proliferation activity in the marine invertebrate, the free-living flatworm Macrostomum sp.. Behavioral Ecology and Sociobiology 56: 420-425 (pdf)

*10. Schärer, L., Joss, G., & Sandner, P. (2004). Mating behaviour of the marine turbellarian Macrostomum sp.: these worms suck. Marine Biology 145: 373-380 (pdf)

9. Schärer, L. & Vizoso, D. B. (2003). Earlier sex change in infected individuals of the protogynous reef fish Thalassoma bifasciatum. Behavioral Ecology and Sociobiology 55: 137-143 (pdf)

*8. Schärer, L. & Ladurner, P. (2003). Phenotypically plastic adjustment of sex allocation in a simultaneous hermaphrodite. Proceedings of the Royal Society of London Series B 270: 935–941 (pdf)

7. Schärer, L., Karlsson, L. M., Christen, M. & Wedekind, C. (2001). Size-dependent sex allocation in a simultaneous hermaphrodite parasite. Journal of Evolutionary Biology 14: 55-67 (pdf)

6. Schärer, L. & Wedekind, C. (2001). Social situation, sperm competition and sex allocation in a simultaneous hermaphrodite parasite, Schistocephalus solidus. Journal of Evolutionary Biology 14: 942-953 (pdf)

5. Binz, T., Reusch, T. B. H., Wedekind, C., Schärer, L., Sternberg, J. M., & Milinski, M. (2000). Isolation and characterization of microsatellite loci from the tapeworm Schistocephalus solidus. Molecular Ecology 11: 1926-1927 (pdf)

4. Wedekind, C., Christen, M., Schärer, L. & Treichel, N. (2000). Relative helminth size in crustacean hosts: in vivo determination, and effects of host gender and within-host competition in a copepod infected by a cestode. Aquatic Ecology 34: 279-285 (pdf)

3. Schärer, L. & Robertson D. R. (1999). Sperm and milt characteristics and male versus female gametic investment in the Caribbean reef fish, Thalassoma bifasciatum. Journal of Fish Biology 55: 329-343 (pdf)

2. Schärer, L. & Wedekind, C. (1999). Lifetime reproductive output in a hermaphrodite cestode when reproducing alone or in pairs: a time cost of pairing. Evolutionary Ecology 13: 381-394 (pdf)

1. Wedekind, C., Strahm, D. & Schärer, L. (1998). Evidence for strategic egg production in a hermaphroditic cestode. Parasitology 117: 373-382 (pdf)

*Corrections and additions

A continuously updated list of corrections, and changes in the taxonomic status of species which are relevant for publications of our group. If you identify any further problems, please report them to lukas.scharer@unibas.ch.


Item to be corrected

Correct version

58. Zadesenets et al. (2016) Macrostomum sp. 8 is now Macrostomum janickei (see ref. 69)
58. Zadesenets et al. (2016) In the legend of Figure 1 the locations of the collection sites 6 and 7 are mixed up. should read "… Palavas-les-Flots (6), Étang de Biguglia (7), …"
57. Janicke et al. (2016) The section "… were held under the monogamy treatment for two generations to reduce potential maternal effects associated with the group size manipulation." should read "… were held as under the monogamy treatment for two generations, but sampling exactly two offspring per pair (i.e. using a middleclass neighbourhood design), to avoid fecundity selection and to reduce potential maternal effects associated with the group size manipulation."
57. Janicke et al. (2016) In Table 1 the F-value for the "Plasticity treatment" effect on "Total sperm length" is incorrectly given as "157.10" should read "10.59"
51. Janssen et al. (2015) Table 1 lists incorrect GenBank accession numbers for the 16S and COI sequences of Stenostomum sp. The GenBank accession numbers for the 16S and COI sequences of Stenostomum sp. should read MH663467 and MH663466, respectively. The given Genbank accession numbers, KP308283 and KP308282, represent 16S and COI sequences of Macrostomum lignano, respectively. See also the published corrigendum added to the end of the PDF.
51. Janssen et al. (2015) Table C lists three coordinates somewhat incorrectly. A corrected version of Table C is provided above.

34. Schärer et al. (2010)

Reference 2 of Table S1 was unexplicably deleted in the last proofing stage; references 2-8 are thus one number higher. should read "2. Sopott-Ehlers B, Ehlers U (1999) Ultrastructure of spermiogenesis and spermatozoa in Bradynectes sterreri and remarks on sperm cells in Haplopharynx rostratus and Paromalostomum fusculum: Phylogenetic implications for the Macrostomorpha (Plathelminthes). Zoomorphology 119:105-115."

34. Schärer et al. (2010)

The volume and page number for Franzén (1956) are incorrect should read "31:355-482."

34. Schärer et al. (2010)

Psammomacrostomum equicaudatum should read "Psammomacrostomum equicaudum"

29. Vizoso et al. (2010)

unrequited inseminations should read "unwanted inseminations"

23. Janicke & Schärer (2009a)

Concentration of protease given as 0.15 µg/ml Correct concentration is 0.15 mg/ml.

16. Schärer et al. (2007).

Concentration of protease given as 0.15 µg/ml Correct concentration is 0.15 mg/ml.

14. Ladurner et al. (2005).

Coordinates for some collection sites are incorrect

The correct coordinates are P1 (N45.69180, E13.13123), X (N45.70247, E13.15637), PS (N45.70383, E13.15793), and UV (N45.63405, E13.07626). See also map in Figure 1 for correct locations.

13. Ladurner et al. (2005)

Macrostomum sp. is now Macrostomum lignano

12. Schärer et al. (2005)

Macrostomum sp. is now Macrostomum lignano

11. Schärer et al. (2004)

Concentration of protease given as 0.15 µg/ml Correct concentration is 0.15 mg/ml.

11. Schärer et al. (2004)

Macrostomum sp. is now Macrostomum lignano

10. Schärer et al. (2004)

Macrostomum sp. is now Macrostomum lignano

8. Schärer & Ladurner (2003)

Macrostomum sp. is now Macrostomum lignano

this page was last updated on Friday, March 25, 2022