DOI: 10.5061/dryad.f6g68
title: Data from: The evolution of reduced antagonism – a role for host-parasite coevolution

description: Why do some host-parasite interactions become less antagonistic over
 evolutionary time? Vertical transmission can select for reduced
 antagonism. Vertical transmission also promotes coevolution between hosts
 and parasites. Therefore, we hypothesized that coevolution itself may
 underlie transitions to reduced antagonism. To test the coevolution
 hypothesis, we selected for reduced antagonism between the host
 Caenorhabditis elegans and its parasite Serratia marcescens. This parasite
 is horizontally transmitted, which allowed us to study coevolution
 independently of vertical transmission. After 20 generations, we observed
 a response to selection when coevolution was possible: reduced antagonism
 evolved in the co-passaged treatment. Reduced antagonism, however, did not
 evolve when hosts or parasites were independently selected, without
 coevolution. In addition, we found strong local adaptation for reduced
 antagonism between replicate host/parasite lines in the co-passaged
 treatment. Taken together, these results strongly suggest that coevolution
 was critical to the rapid evolution of reduced antagonism.
description: Frequency of the
 ruby-throated phenotypeFrequency of the
 ruby-throated phenotype assayed in different combinations of host and
 parasite lines. "Pairing" indicates the specific pairing of host
 and parasite lines being made. "Host" and "Parasite"
 columns provide additional details. In these columns, Ancestor and
 Ancestor-sm2170 refer to the ancestral populations of host and parasite,
 respectively, used to initiate experimental evolution. Similarly, control,
 singly, and co-passaged refer to the products of 20 generations of
 experimental selection under the Control, Singly-passaged, and Co-passaged
 treatments, respectively. "Line" indicates the replicate lineage
 being tested, and "Replicate" indicates the replicate assay
 plate within each replicate lineage. "Frequency" indicates the
 proportion of adult hermaphrodites displaying the ruby-throated phenotype
 in the assay population.1-Frequency.csvFecundity of ruby-throated hermaphroditesFecundity of ruby-throated hermaphrodites, resulting from different combinations of host and parasite lines. "Pairing" indicates the specific pairing of host and parasite lines being made. "Host" and "Parasite" columns provide additional details. "Line" indicates the replicate lineage being tested, and "Replicate" indicates the replicate assay plate within each replicate lineage. For each replicate assay plate, 10 hermaphrodites were observed - column "Hermaphrodite." The number of offspring produced by each hermaphrodite is reported in the column "Offspring."2-Fecundity.csvFecundity of healthy hermaphroditesFecundity of healthy hermaphrodites, assayed in otherwise the same way as fecundity of ruby-throated hermaphrodites. "Host" indicates the host experimental evolution treatment being assayed, and "Line" the replicate lineage. Fifteen hermaphrodites were sampled per replicate lineage, identified under "Hermaphrodite." The number of offspring produced by each hermaphrodite is reported in column "Offspring."3-Fecundity_healthy.csvMortality rateMortality rate induced by parasite populations following experimental evolution. All parasite populations were evaluated against the ancestral host lineage of matching number. “Parasite” indicates the parasite experimental evolution treatment being assaying, and “Line” the replicate lineage. “Replicate” indicates the replicate assay plate. “Mortality_Rate” gives the proportion of hosts found to be dead or morbid following 24 hours of exposure to the parasite population.4-Mortality.csvLocal AdaptationLocal adaptation data. Fecundity of hosts from the Co-passaged treatment paired with sympatric and allopatric parasites from the Co-passaged treatment. A “1” in the “Sympatric” column indicates a sympatric pairing; “0” indicates allopatric. “Line_host” and “Line_parasite” indicate the replicate lineages of host and parasite, respectively, combined in the assay. “Replicate” identifies the 15 hermaphrodites assayed for fecundity per pairing. The number of offspring produced by each hermaphrodite is reported in the column “Offspring.”5-LocalAdaptation.csv