I'm not sure specifically as I haven't read the exact 'Penguin Island Novel', but likely there would be some penguin leaders or important individuals within the penguin community.
In 'Penguin Island Novel', the main characters could be a group of penguins. There might be an adventurous young penguin who is always exploring new parts of the island. There could also be an older, wiser penguin that imparts knowledge and wisdom to the younger ones. And perhaps a mother penguin who is focused on raising her chicks in the difficult island environment.
Well, in 'Penguin Island Novel', it may be centered around the survival theme. Penguins have to face various challenges like harsh weather, finding food, and protecting their young in the island setting. This could be a major theme as it affects their daily existence and the development of their community on the island.
Well, from the title, one main character is likely the penguin. And since death is in the title too, death could be another main character, maybe personified as some kind of entity.
The main characters are usually the penguin avatars. There could be a brave little penguin who is always ready for an adventure, or a friendly penguin who loves to make new friends.
There might be a castaway who has to adapt to the island life. There could also be a group of sailors who end up on the island by accident. Among them, there may be a leader figure who tries to keep everyone in order and find a way to get off the island. Additionally, there could be a local on the island who helps or hinders the outsiders depending on the story's direction.
Most likely the penguins themselves. There could be a male penguin who is the main character, perhaps on a journey to find food for his family.
I think the main characters would be the young penguins. Alongside them, their parents could also be important characters as they play a big role in taking care of the kids, teaching them to swim and find food. And perhaps there could be some friendly seabirds or other small Antarctic animals that interact with the penguin kids in the story.
Without having read 'The Island' by Benchley, it's difficult to name the exact main characters. But it's common in novels set on islands to have a protagonist who is a bit of an outsider. Maybe someone who has come to the island to escape their past or in search of something. There could also be a character who is native to the island and acts as a guide or a source of knowledge about the island's secrets.
There could be immigration officers or officials at Ellis Island as main characters too. They might play a role in determining the fates of the immigrants, and the novel could explore their perspectives, like how they deal with the flood of new arrivals and the rules they have to enforce.
There could be a group of friends who decide to visit the island together. One of them might be the leader type, always making decisions. Another could be the comic relief, always cracking jokes even in difficult situations. And perhaps there's a more mysterious character whose past is somehow related to the island.
There could be a variety of characters. There might be a strong and resourceful man who is good at building shelters and finding food. There could also be a woman with a kind heart who takes care of the others emotionally, and perhaps a child who brings out the protective side of the other characters.