The Happy Meal launched in Sweden last week and will be introduced throughout Europe in the coming months. It is expected to arrive in the UK next March.
The toys given away with the meals are based on endangered species, including the giant panda, the polar bear and the black rhinoceros. Each comes with a little leaflet carrying information about how much the population has declined, and where in the world the animal lives, as well as the .
McDonald's will be making what it called a "significant financial contribution" towards the charity Conservation International, which aims to protect life on Earth.
McDonald's said that the new Happy Meal had been designed based on research from Just Kids Inc's Global Kid Study, which showed that children daydream about helping others and are becoming more altruistic.
The Happy Meal has become the target of criticism as the government and health campaigners debate the best way to beat child obesity. Liverpool city council went so far as to suggest a ban on their sale in the city.
In response to criticism, McDonald's has added healthier options such as fruit, water and yoghurt, alongside the traditional fries and fizzy pop. Reports say that it is developing a range of educational toys, such as puzzles and brainteasers to go with Happy Meals in 2009.