Peter Downes was the second son of Edward Downes (d.1748) of Shrigley and Worth in Cheshire and his wife Bridget, daughter of the Rev. Philip Egerton. Upon the death of his elder brother, John Downes (1723-1764), Peter Downes succeeded to the property in Cheshire. He married firstly Lucy, widow of Capt. David Clayton, at Calcutta on 2 September 1760; she died, and was buried there on 22 November 1765. Within a year he had returned to England and on 13 November 1766 at St. Christopher Le Stocks, London, married his second wife Elizabeth, who had been baptised at the same church on 5 April 1744. It is probable that he purchased the eggs on his journey home from India prior to his second marriage in 1766 and had them mounted to commemorate the event. Peter Downes died in Cheshire in 1791.