Final answer:
The specific percentage of endemic species in the Antarctic compared to the Arctic is not provided in the information. However, both regions have unique, adapted endemic species, with the Antarctic covered by a vast ice sheet and the Arctic experiencing shifts in species distributions due to changing ice environments.
Step-by-step explanation:
The question pertains to the comparison of endemic species percentages between the Antarctic and the Arctic. Unfortunately, the provided information does not directly supply data comparing these two regions. However, it is important to note that both the Antarctic and the Arctic have unique ecosystems with species that are highly adapted to their cold environments. In the case of Antarctica, approximately 98% is covered by an ice sheet, holding about 70% of Earth's fresh water, which hints at a unique, but not necessarily diverse, endemic ecosystem due to its harsh conditions. In contrast, the Arctic has seen considerable shifts in species distribution due to the decrease in ice area and thickness, affecting the life histories of endemic species like the polar bear. Meanwhile, biodiversity hotspots identified by Conservation International cover just 2.3% of Earth's surface but contain 42% of the terrestrial vertebrate species and 50% of the world's plants, showcasing the concentration of endemic species in specific regions, although not directly related to polar regions.