Final answer:
The phylogenetic relationship of brown bears to polar bears is of close genetic relatives with a shared ancestor. ABC brown bears would appear very close to polar bears on a phylogenetic tree due to their genetic similarities and shared lineage.
Step-by-step explanation:
The phylogenetic relationship between brown bears and polar bears indicates that they share a common ancestor, making them closely related species within the bear family. Specifically, ABC brown bears would be positioned close to polar bears in a phylogenetic tree, demonstrating their close genetic relationship. However, they are distinct species adapted to different habitats. When drawing a phylogenetic tree, polar bears would be shown as a sister group to the ABC brown bears, with all brown bears forming a monophyletic group separate from other bear species, such as black bears. Due to climate change and the resulting habitat overlap, the Arctic brown bears (which are a subset of brown bears) and polar bears have been known to interbreed, producing hybrids sometimes referred to as 'grolar bears'.