Chase-away evolution maintains imperfect mimicry despite rapid evolution of mimics

We studied a brood parasite-host system to test the fundamental hypothesis that deceptive mimics evolve to resemble models, selecting in turn for models to evolve away from mimics (“chase-away evolution”), and whether such reciprocal evolution maintains imperfect mimicry over time. We quantified the pattern complexity of host and parasitic eggs; complexity of egg patterns predicts egg rejection in the host species. Over only 50 years, parasites evolved towards hosts and hosts evolved away from parasites. This resulted in no detectible increase in mimetic fidelity. Our results reflect rapid adaptive evolution in wild populations and show that chase-away evolution in models can counteract even rapid evolution of mimics, resulting in the persistence of imperfect mimicry., Eggs were photographed in linearised RAW format, in shade with a Nikon D90 camera with a 60 mm Micro-Nikkor lens.
Complexity was quantified exactly as described in Dixit et al., 2022 (Visual complexity of egg patterns predicts egg rejection according to Weber's law. Proc. R. Soc. B. 289: 20220710. https://royalsocietypublishing.org/doi/10.1098/rspb.2022.0710)., , # Title of Dataset: Rapid evolution of a brood parasites egg pattern does not lead to large increases in mimetic fidelity.

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This dataset contains 1 excel file as well as R code detailing statistical analyses.

1. historical_complexities_full_priniacf.csv: a dataset detailing complexity scores for cuckoo finch and prinia eggs.

## Description of the Data and file structure

historical_complexities_full_priniacf.csv:

**Column names**

Year_Nest_Egg_NestIn : Individual code for each egg
Year: Year in which egg was laid
Nest: Nest ID in which egg was laid
Egg: Egg ID
NestIn: Nest ID in which egg was placed (in cases where egg was moved to another next as part of other experiments)
Complexity_a: complexity score for a single image of the egg
Complexity_ac: average complexity score across 2 images of 'either side' of the egg - see description in Dixit, T., Apostol, A. L., Chen, K.-C. et al. (2022). Visual complexity of egg patterns predicts egg rejection according to Webers law. Proceed...