Chapter 12: Mole bears
The ancestors of today's modern grizzly bears where some of the largest creatures of their time. During the time when they were on the brink of extinction several populations of these cave bear's ancestors journeyed to the Croodaceous skull island 40,000 years ago, and have adapted to underground living on an even larger scale as they have evolved the ability to burrow underground like giant moles hence the name. Since then they have evolved huge claws, Star nosed mole like snout sensors and a more carnivorous diet, due to vegetation competition. They are still omnivorous but the only vegatation they eat are roots and some berries for nutrients. the main thing they prey on are Girelephants, Giant mammoths that migrate a lot. They wait for herds to pass underground and when they sense on lagging behind they erupt from the ground like polar bears and drag them down. This method helps them hunt, not only the giant mammoths but most large animal species on the island even some sauropods. It wouldn't be the hardest thing ever since the size the bears have grown to be 12 ft tall on all fours and 27 ft tall on both hind legs, not to mention being much heavier than their ancestors, potentially weighing more than an African elephant. There competition with cave lions is still fierce but it is an even match.