of Pisistratus, a member of the influential Peisistratids family and rival clan to the Alcmaeonidae, the aforementioned Megacles married his daughter to the tyrant, but when the tyrant refused to have children with her, Megacles and his allies banished him. Later the Alcmaeonids would claim to have been exiled following Pisistratus' return in 546 BC, so as to distance themselves from possible accusations of complicity, but epigraphic evidence in fact proves that Cleisthenes was archon for the year 525–24 BC. Megacles was able to marry (for a second or third time) Agarista, the daughter of the tyrant Cleisthenes of Sicyon. They had two sons, Hippocrates and another Cleisthenes, this one the reformer of Athenian democracy. Hippocrates' daughter was Agariste, the mother of Pericles. Contributions to Athenian democracy: Cleisthenes The Alcmaeonid Cleisthenes overthrew Hippias, the son and successor of Pisistratus, in 508 BC. Herodotus claimed in his The Histories that the Alcmaeonidae specifically hated tyranny, and that they were more esteemed and highly honored than any other clan for ridding Athens from it. Cleisthenes had bribed the oracle at Delphi (which the Alcmaeonidae had helped to build while they were in exile) to convince the Spartans to help him, which they reluctantly did. He was, at first, opposed by some who felt the famous curse made the Alcmaeonidae ineligible to rule; the Spartan king Cleomenes I even turned against Cleisthenes and the latter was briefly exiled once more. However, the citizens called for Cleisthenes to return, as Cleisthenes achieved support from the masses due to his calls for a more democratic system against his rival Isagoras, thus giving more power to the people, and the restored Alcmaeonids were responsible for laying the foundations of Athenian democracy. A few of the contributions that the Alcmaeonid Cleisthenes helped develop in Athens included the shifting of political organization from the four traditional tribes, which were based on family relations and which formed the basis of the upper class Athenian political power network, into ten tribes according to their area of residence (their deme), which would form the basis of a new democratic power structure. Additionally, through Cleisthenes' reforms, the people of Athens endowed their city with isonomic institutions—equal rights for all citizens (though only men were citizens)—and established ostracism as a punishment. He also established sortition—the random selection of citizens to fill government positions rather than kinship or heredity, a true test of real