According to current data on infectious diseases, which statement about new bacterial species and marine mammals is most accurate?

Introduction / Context:
Infectious diseases affect humans, domestic animals, and wildlife, including marine mammals such as seals, dolphins, and whales. Microbiologists and veterinarians study the bacteria, viruses, and other pathogens that cause disease in these animals. New research and improved detection methods continue to reveal previously unknown species of bacteria and new host pathogen relationships. This question checks whether you understand that scientific knowledge about bacteria and infections is still expanding and that marine mammals can both carry and suffer from infectious diseases, just as terrestrial animals do.

Given Data / Assumptions:

• The question refers to data collected to date on infectious diseases and bacterial species.
• Statements involve wild or marine animals, humans, and pathogens that might infect more than one host species.
• We assume a basic understanding that microorganisms are very diverse and that many species remain undiscovered.
• The focus is on what current evidence suggests, not on unrealistic absolute statements.

Concept / Approach:
Microbial diversity is enormous, and researchers continuously discover new bacterial species, especially in under studied environments such as oceans, deep sea vents, and wildlife populations. Marine mammals are exposed to a variety of bacteria through water, prey, and environmental contamination. They can suffer from infectious diseases caused by bacteria, viruses, and parasites. Some pathogens can infect both humans and marine mammals, demonstrating zoonotic or reverse zoonotic transmission. Therefore, any statement claiming that humans and marine mammals cannot share pathogens or that marine mammals do not get infectious diseases at all contradicts current scientific evidence. The only statement consistent with ongoing discovery and observation is that new species of bacteria may still be found in wild animals, including marine mammals.

Step-by-Step Solution:
1. Recognize that scientists continue to discover new bacteria in many environments, including soil, oceans, and animal bodies.2. Understand that wild animals, such as marine mammals, can host unique bacterial communities that have not yet been fully cataloged.3. Note that some bacteria and other pathogens have wide host ranges and can infect more than one species, including humans and marine mammals.4. Realize that marine mammals are known to suffer from infectious diseases such as pneumonia, skin infections, and systemic bacterial infections.5. Therefore, any statement that claims marine mammals do not get infections or that they cannot share pathogens with humans is not accurate.6. The statement that new bacterial species may be discovered in wild animals fits well with current scientific understanding and ongoing research.

Verification / Alternative check:
Reports from marine biology and veterinary science describe numerous infectious outbreaks in seals, sea lions, dolphins, and whales, including bacterial infections associated with pollution, stress, or changing environmental conditions. Studies of microbiomes show that many bacterial species on and inside animals are still not fully identified. Additionally, documented cases exist where certain bacteria or viruses are detected in both humans and marine mammals, indicating shared or cross species pathogens. These observations confirm that marine mammals do get infectious diseases and that humans can in some cases share pathogens with them. Therefore, the only cautious and scientifically sound statement is that more bacterial species remain to be discovered in wildlife.

Why Other Options Are Wrong:
Option B, which claims that humans and marine mammals cannot be infected by the same pathogens, is wrong because cross species infections have been documented. Option C, stating that marine mammals do not get infectious diseases, is clearly false because many diseases in these animals are described in scientific literature. Option D, claiming that all bacteria have already been discovered on land, is incorrect because microbial diversity is far from fully known, and new species are still being described regularly. Thus, only the option about discovering new bacteria in wild animals is consistent with evidence.

Common Pitfalls:
Students sometimes assume that because the ocean is vast, marine mammals are somehow protected from infection, but in reality they face many disease risks. Another pitfall is to treat current knowledge as complete and to believe that most or all bacteria have already been discovered. In science, knowledge is always expanding, and especially in microbiology there is wide recognition that many species remain undescribed. Keeping in mind the ongoing nature of scientific discovery helps avoid choosing options that make absolute claims which cannot be justified.

Final Answer:
Current data indicate that new species of bacteria may be discovered in wild and marine animals, while marine mammals do in fact suffer from infectious diseases and can sometimes share pathogens with humans.