Final answer:
To test the issue of gene versus species trees, one can investigate inheritance patterns, analyze genetic data in conjunction with phylogenetic trees, and observe changes in characteristics through breeding experiments.
Step-by-step explanation:
Testing the issue of gene versus species trees can be done through various methods. One way is to investigate inheritance patterns in an organism of choice by performing genetic crosses and comparing observed phenotypic ratios with the expected ratios based on Mendelian inheritance. Another method is to analyze genetic data sets in conjunction with phylogenetic trees or cladograms to determine evolutionary history and speciation. Additionally, scientists can breed different groups in the same or different environments to observe changes in their characteristics over several generations.
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