Final answer:
In determining a species' likely mating system, one must consider the advantages of different strategies. Monogamous systems, where one male and one female pair for a season or lifetime, are characterized by shared parental investment and potentially by mate-guarding, male-assistance, and female-enforcement strategies. This system aligns with the first option, where a male and female partner for life.
Step-by-step explanation:
To determine the more likely mating system in a given species, we need to consider the various mating strategies and how they manifest in the animal kingdom. Monogamous systems involve one male and one female pairing for at least one breeding season; sometimes this bond can last a lifetime. Examples include the gray wolf and many bird species, where both parents provide care for their offspring, making monogamy advantageous for the survival of the young. This can be explained by the mate-guarding hypothesis, male-assistance hypothesis, and female-enforcement hypothesis.
In contrast, polygynous and polyandrous systems involve multiple mating events. Polygyny, where one male mates with multiple females, and polyandry, where one female mates with multiple males, have different implications for parental investment and offspring survival. Given that monogamy is characterized by significant parental investment and mate guarding, it would align with the first mating system outlined in your question, where a male and female partner for life.