Biology Regents Practice Exam

What is the most likely basis for the new classification of the three types of squid?

1. Analysis of a greater number of squid carcasses

2. Feeding habits of the three different types

3. Number of newly found squid fossils

4. DNA present in the cells of the squid

The correct answer is: DNA present in the cells of the squid

The new classification of the three types of squid is most likely based on the DNA present in their cells. This approach aligns with modern biological classification methods, which increasingly rely on genetic information to categorize organisms. Analyzing DNA allows scientists to understand the evolutionary relationships and genetic similarities or differences between species more accurately than morphological characteristics alone. DNA evidence can reveal how closely related different squid species are, often leading to reclassification that reflects their evolutionary lineages. Unlike the other options, which may involve observational or historical data, DNA analysis provides concrete molecular evidence that can definitively establish relationships among the squid types based on their genetic makeup. This specificity and accuracy make it a powerful tool in modern taxonomy.