Final answer:
Based on the cladogram, one can deduce whether a species has gained or lost specific traits after diverging from the most recent common ancestor by looking for traits that are present or absent compared to related species. Option a represents an evolutionary gain, while options b and c represent evolutionary losses. Option d suggests convergent evolution, where similar traits develop independently in unrelated species.
Step-by-step explanation:
To determine what evolutionary events have occurred after the split from a most recent common ancestor (MRCA) based on a cladogram, one needs to consider the traits represented by various symbols on the cladogram. A cladogram is a diagram that shows relationships among species based on shared derived characters. When analyzing a cladogram for evolutionary history, consider the following:
- If a species has a trait that others stemming from the same ancestor do not, it's likely this trait was gained after the split. This would correspond to option a, the evolutionary gain of the trait represented by a triangle.
- If the species lacks a trait that all other related species from the MRCA have, it suggests the loss of that trait, corresponding to option b or option c, the loss of the trait represented by a diamond or a square, respectively.
- Convergent evolution is indicated when unrelated species develop similar traits independently. This can make it appear as though they share a recent common ancestor when they do not. This corresponds to option d, the convergent evolution of the trait represented by the circle.
Thus, to provide the most parsimonious explanation for the evolution of the species on the card in question, one should assess which traits it has or lacks compared to other species in the cladogram that share the same MRCA.