Experimental interspecific hybridization in Daphnia

TY - JOUR

T1 - Experimental interspecific hybridization in Daphnia

AU - Schwenk, K.

AU - Bijl, M.

AU - Menken, S.B.J.

N1 - Reporting year: 2001 Metis note: 2584; CL; AFW; file:///L:/Endnotedatabases/NIOOPUB/pdfs/Pdfs2001/Schwenk_ea_2584.pdf

PY - 2001

Y1 - 2001

N2 - Hybridization is a common phenomenon in Daphnia (Cladocera; Anomopoda); interspecific hybrids have been found between several species and hybrids are found in many European lakes. Although much information on the morphology, ecology and genetics of hybrids is available, little is known about the level of reproductive isolation among species or about the relative fitness of hybrids and parental species. In order to facilitate studies on differentiation and speciation processes and comparative experimental studies on hybrids and recombinant genotypes, we present the first successful laboratory crossing experiments of two different Daphnia species, D. galeata and D. cucullata. Males and sexual females from two D. galeata and two D. cucullata clones were reciprocally crossed, juveniles hatched from resting eggs and reared until maturity. Hatching and juvenile survival rates of hybrids were relatively low (12.1% and 24%, respectively). D. galeata and D. cucullata clones vary in their level of successful interspecific matings and in the number of subsequent offspring. In general, hybrid crosses between D. cucullata females and D. galeata males were more successful than reciprocal crosses. [KEYWORDS: interspecific hybridization; Daphnia; laboratory hybrids; Hyalodaphnia; reproductive isolation; ephippia Hybrid species complex; life-history variation; resting eggs; lake-daphnia; cladocera; population; crustacea; evolution; pulex; mitochondrial]

AB - Hybridization is a common phenomenon in Daphnia (Cladocera; Anomopoda); interspecific hybrids have been found between several species and hybrids are found in many European lakes. Although much information on the morphology, ecology and genetics of hybrids is available, little is known about the level of reproductive isolation among species or about the relative fitness of hybrids and parental species. In order to facilitate studies on differentiation and speciation processes and comparative experimental studies on hybrids and recombinant genotypes, we present the first successful laboratory crossing experiments of two different Daphnia species, D. galeata and D. cucullata. Males and sexual females from two D. galeata and two D. cucullata clones were reciprocally crossed, juveniles hatched from resting eggs and reared until maturity. Hatching and juvenile survival rates of hybrids were relatively low (12.1% and 24%, respectively). D. galeata and D. cucullata clones vary in their level of successful interspecific matings and in the number of subsequent offspring. In general, hybrid crosses between D. cucullata females and D. galeata males were more successful than reciprocal crosses. [KEYWORDS: interspecific hybridization; Daphnia; laboratory hybrids; Hyalodaphnia; reproductive isolation; ephippia Hybrid species complex; life-history variation; resting eggs; lake-daphnia; cladocera; population; crustacea; evolution; pulex; mitochondrial]

U2 - 10.1023/A:1017594325506

DO - 10.1023/A:1017594325506

M3 - Article

SN - 0018-8158

VL - 442

SP - 67

EP - 73

JO - Hydrobiologia

JF - Hydrobiologia

IS - 1-3

ER -