The evolution of a placenta accelerates the evolution of post-copulatory reproductive isolation

The evolution of placentation is predicted to intensify intergenomic conflicts between mothers and offspring over optimal levels of maternal investment by providing offspring opportunities to manipulate mothers into allocating more resources. Parent-offspring conflicts can result in the evolution of reproductive isolation among populations when conflicts resolve in different ways. Postzygotic reproductive isolation is hypothesized to evolve more rapidly following the evolution of placentation due to the predicted increase in conflict. We tested this hypothesis by performing interpopulation crosses within placental and non-placental species of Poeciliopsis to determine if the relationship between genetic distance and measures of postzygotic reproductive success differed as function of reproductive mode. We did not observe any differences in offspring viability or sterility among crosses. Offspring size declined rapidly as a function of interpopulation genetic distance within the placenta..., We assessed interfertility among populations from three species of Poeciliopsis. We selected Poeciliopsis prolifica and Poeciliopsis infans to represent a paired comparison of closely related placental and non-placental species from the same clade, respectively (Reznick, Mateos et al. 2002, Pollux, Meredith et al. 2014). Poeciliopsis gracilis, was included as an additional non-placental species from a separate clade (Reznick, Mateos et al. 2002). We established lab populations at the University of California Riverside with 15 wild-caught pregnant females and five adult males from 4 populations of P. prolifica, 4 populations of P. nfans, and 2 populations of P. gracilis (Table S1) between 2014-2015. Fish from an additional population of P. gracilis collected in 2004 and maintained in 3 stock tanks were also included (Table S1). To ensure allopatry, we collected each population from a different river (Figure 1; Table S1). Schrader et al. (2013) found in their crosses among populations of ..., , # Poeciliopsis Population Cross Data

[https://doi.org/10.5061/dryad.wpzgmsbzg](https://doi.org/10.5061/dryad.wpzgmsbzg)

## Description of the data and file structure

Lab stocks were established from 11 populations of wild caught fish. Environmental measures (i.e. site data) was recorded at time of collection for each population. F1 individuals found in lab established stocks were raised to sexual maturity and used in intra- and interpopulation mating crosses (i.e. cross data).  Instances where F1 females did not make the first time were recorded (i.e. binary_recrosses).  Tissues from wild caught females were used for ddRADseq genomic sequencing processed using stacks pipeline.

### Files and variables

#### File: binary\_recrosses.csv

**Description:** Contains all outcomes for intra- and interspecific crosses of Poeciliopsis

##### Variables

* cross.type: Denotes populations of origin for female and male (i.e. OA female x OA male)
* success: 0 denotes unsuccessful mating from cross...