Evidence for Galaxy Formation at High Redshift.

We present new evidence that simple evolutionary models where the star-formation rate in galaxies increases exponentially with redshift but the space density of galaxies remains constant with redshift, give very precise fits to the number count of Lyman break, UV dropout, galaxies detected at z≈3. This suggests a possible identification of the brightest Lyman break galaxies at z≈3 with the evolved population of bright spiral galaxies at the present day. The models also fit well the bright B dropout galaxies at z≈4, although the models start to overestimate the observed numbers of dwarf galaxies at this redshift. This suggests that although we may be detecting the epoch of formation of dwarf galaxies at z≈4, the epoch formation of bright galaxies lies at still higher redshift. Finally, there are significant numbers of galaxies now being detected by R dropout in the range 5.3<z