How the Thalassocnus Sloths Survived the Pliocene

In the alternative timeline where some members of the genus Thalassocnus, colloquially referred to as the Sea Sloths, survived past the Pliocene epoch, the first factor that must be considered is their evolution in the face of changing global climates. The Pliocene epoch ended slightly over 2.5 million years ago with a period of global cooling. The Sea Sloths, as marine herbivores that thrived in warm waters, were forced to continue their shift further southward. Focusing on their primary habitat—the coastal areas of the closest land—South America in their case, or even the warmer portions of the Antarctic Ocean, these creatures existed in an ecosystem whereby they were challenged by the rising dominance of the Sirenians, specifically the manatees and dugongs. As Sea Sloths were primarily bottom feeders that used their specially adapted clawed limbs to rake up seagrass and algae, competition arose. However, in order to survive, natural selection played its course. The Sea Sloths began to exhibit genetic changes that allowed them to efficiently digest and extract energy from other sources of sea vegetation, therefore expanding their dietary range. Physiologically, too, the marine sloths might have developed more streamlined bodies and specialized appendages for deeper diving and faster swimming, making them agile in the water and proficient at dodging or counteracting predators. Interbreeding with the more dominant sirenians might occur, leading to a new hybrid species that takes advantage of traits from both parental lineages. This would lead to an array of unexpected and divergent features among offspring, potentially evolving into entirely new species in the face of continuing environmental pressures. This could result in marine sloths that look quite different to both traditional sloths and sirenians but still retain certain traits. They might become communal creatures for shared protection and food resources, changing their typically solitary nature. Social behaviors could become more complex, with potential for intricate communication techniques or cooperative living environments to survive the competition and changing oceanic climates. In summary, the survival of the Thalassocnus lineage into the modern seas would most likely result in a world with a diversity of marine mammal species even richer than what we observe today. Granted, many of these new species might not look much like the traditional image of a sloth, but they would still harbor a piece of that ancient heritage within their DNA as a testament to their incredible journey through evolutionary time.