The article presents a well-researched study on the ecological roles of sharks over millions of years, based on the analysis of fossilized shark teeth. The primary claims about the decline in functional diversity and the historical roles of sharks are supported by specific examples such as Otodus megalodon as an apex predator. However, the article could benefit from more detailed explanations of the methodologies used to quantify 'functional space' and 'functional redundancy.' The claim that modern sharks have lost 44% of their functional richness is significant and aligns with existing research, though it requires more direct citations to the original study by Cooper and Pimiento for full verification.

The article primarily focuses on the scientific findings related to shark functional diversity without delving deeply into opposing viewpoints or alternative interpretations. While it provides a comprehensive look at the research findings, it lacks perspectives from other scientists or stakeholders who might offer different insights into the implications of the study. The article could enhance its balance by including views from marine conservationists, policymakers, or industries affected by shark populations, which would provide a more rounded discussion.

The article is well-written, with clear and concise language that makes complex scientific concepts accessible to a general audience. The logical flow from historical analysis to modern implications is well-structured, and the use of specific examples like different shark species' roles helps illustrate the points effectively. The tone is neutral and informative, which aids in comprehension and engagement.

The article cites a global study by reputable scientists, Dr. Jack A. Cooper and Dr. Catalina Pimiento, which lends credibility to the information presented. However, the article does not provide direct links to the original research paper or additional scientific literature that could substantiate the claims made. Including a broader range of sources or direct citations would enhance the source quality by allowing readers to verify the information independently.

While the article effectively communicates the main findings of the research, it lacks transparency in terms of explaining the methodologies and data sources in detail. The discussion of how 'functional diversity' and 'functional redundancy' are measured is somewhat opaque, which could leave readers questioning the basis of these conclusions. Greater transparency about the data collection process and the analytical techniques used would improve the article's trustworthiness.