You can tell how old a male lion is by the appearance of his mane. As male lions age, their long manes of fur begin to darken. Elderly lions may also experience graying of their mane’s fur as they reach their final years. The texture of the fur may also be used to determine lions’ age, as their fur becomes more brittle and may have a duller appearance over time. Not all male lions have manes though—in the hottest climates, manes of fur would cause the animals to overheat. Therefore, other factors are used to estimate their age, such as more pronounced footsteps that indicate reduced eyesight and a decrease in the appearance of muscle tone.
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