People are not the only residents living large in the eastern suburbs – spiders at Tamarama Beach are fatter and more fertile than their rural counterparts.

While studying the ways animals adapt to city life, ecologist Lizzy Lowe discovered golden orb weaving spiders thrive in Sydney's concrete jungle.

Golden orb spiders are fatter in the city. Credit:Anthony Johnson

''They seem to really enjoy living by the coast,'' Ms Lowe, from the University of Sydney, said.

The more urbanised and wealthier the suburb, the fatter the golden orbs found in nearby gardens and pockets of bushland, she said.