Which type of evidence most strongly supports grouping tarsiers with haplorrhines rather than strepsirrhines?

• A. Molecular genetic data showing closer DNA similarity between tarsiers and other haplorrhines
• B. Nocturnal lifestyle shared with most strepsirrhines
• C. Presence of a moist rhinarium (wet nose) in tarsiers
• D. Grooming claw on the second toe, a trait found in strepsirrhines

Answer: (A)

Verified step by step guidance

1. Understand the context of the question: The problem is asking about evidence that supports the classification of tarsiers as haplorrhines rather than strepsirrhines. Haplorhines and strepsirrhines are two major suborders of primates, distinguished by various anatomical, behavioral, and genetic traits.
2. Review the traits mentioned in the options: The options include molecular genetic data, nocturnal lifestyle, presence of a moist rhinarium, and grooming claw. Each of these traits needs to be evaluated for its relevance and strength in supporting the classification.
3. Consider molecular genetic data: Molecular genetic evidence, such as DNA similarity, is one of the strongest forms of evidence in modern biology for determining evolutionary relationships. If tarsiers share closer DNA similarity with haplorrhines, this strongly supports their grouping with haplorrhines.
4. Evaluate anatomical and behavioral traits: Traits like nocturnal lifestyle, moist rhinarium, and grooming claw are useful for understanding adaptations but are less definitive for determining evolutionary relationships. For example, a moist rhinarium is characteristic of strepsirrhines, but its presence in tarsiers could be due to convergent evolution rather than shared ancestry.
5. Conclude based on evidence strength: Molecular genetic data provides direct evidence of evolutionary relationships and is considered more reliable than anatomical or behavioral traits, which can be influenced by environmental factors or convergent evolution. Therefore, molecular genetic data is the strongest evidence for grouping tarsiers with haplorrhines.