Avian clutch size of increasing clutch size with increasing latitude. The proximate and ultimate causes for this pattern have been a subject of intense debate involving the ideas of group and individual selection. David Lack observed a direct relationship between latitude and avian clutch size. Birds near the equator laid approximately half as many eggs as those that resided in northern temperate habitats. He observed an increasing clutch-size from the equator towards the poles (something he referred to as the “latitude trend”) for many passerine (perching) birds, near-passerine (tree-dwelling) birds and in various other groups: Strigiformes, Falconiformes, Ciconiiformes, Laridae, Ralliformes, Galliformes, Podicipedifomes, and
The Conference of the Birds x 11,4 cm. The Conference of the Birds The Conference of the Birds or Speech of the Birds (, "Manṭiq-uṭ-Ṭayr", also known as "Maqāmāt-uṭ-Ṭuyūr"; 1177) is a celebrated literary masterpiece of Persian literature by poet Farid ud-Din Attar, commonly known as Attar of Nishapur. The title, which is in Arabic, is taken directly from the Qur’an, 27:16, where Sulayman (Solomon) and Dāwūd (David) are said to have been taught the language, or speech, of the birds ("manṭiq al-ṭayr"). In the poem, the birds of the world gather to decide who is to be their sovereign, as they have none. The