A children’s book about two male penguins who hatched and raised a young female named ‘Tango’ has topped a list of the most challenged books in public and school libraries in the US.

And Tango Makes Three, by Justin Richardson and Peter Parnell is based of the true story of Roy and Silo, who formed a couple in New York’s Central Park Zoo.

They attempted to hatch a rock, which was replaced by a rejected egg from a mixed gender couple by zookeepers.

They then adopted the baby penguin Tango as their own.

The book is accused of promoting homosexuality and being ‘anti-family’ as well as unsuitable for its age group.

It has attracted great controversy in US states with parents in Illinois and Missouri requesting the book be placed in a restricted or non-fiction section of the library.

In Charlotte, North Carolina, a superintendent of certain schools ordered the book removed completely from school libraries.

The Office for Intellectual Freedom of the American Library Association has produced a list of books that have attracted written complaints or ‘challenges’ from library users in 2006.

The list of 546 consists of books that libraries have been asked to remove from the shelves.

Three other books in the top ten listed ‘homosexuality’ as a reason for their withdrawal requests.

These were:

- the Gossip Girls series by Cecily Von Ziegesar for homosexuality, sexual content, drugs, unsuited to age group, and offensive language;

- Athletic Shorts by Chris Crutcher for homosexuality and offensive language;

- The Perks of Being a Wallflower by Stephen Chbosky for homosexuality, sexually explicit, offensive language, and unsuited to age group.