ellipticals had a pBzK as a main progenitor.
author:
- |
    W. G. Hartley$^{1}$[^1], K. P. Lane$^{1}$, O. Almaini$^{1}$, M. Cirasuolo$^{2}$, S. Foucaud$^{1}$, C. Simpson$^{3}$, S. Maddox$^{1}$, I. Smail$^{4}$, C. J. Conselice$^{1}$, R. J. McLure$^{2}$, J. S. Dunlop$^{5}$\
    $^{1}$School of Physcis and Astronomy, University of Nottingham, University Park, Nottingham NG7 2RD\
    $^{2}$SUPA[^2] Institute for Astronomy, University of Edinburgh, Royal Observatory, Edinburgh EH9 3HJ\
    $^{3}$Astrophysics Research Institute, Liverpool John Moores University, Twelve Quays House, Egerton Wharf, Birkenhead CH41 1LD\
    $^{4}$Institute for Computational Cosmology, Department of Physics, Durham University, Durham DH1 3LE\
    $^{5}$Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Rd., Vancouver, B.C., V6T 1Z1, Canada\
bibliography:
- 'mn-jour.bib'
- 'papers\_cited\_by\_KL.bib'
title: 'The clustering and abundance of star-forming and passive galaxies at $z \sim 2$'
---

\[firstpage\]

Infrared: galaxies – Cosmology: large-scale structure – Galaxies: High Redshift – Galaxies: Evolution – Galaxies: Formation.

Introduction
============

There is growing evidence to support the view that the most massive objects in the Universe were the first to assemble and complete their star formation (@Kodama_etal:2004 [@Thomas_etal:2005; @DeLucia_etal:2004; @Bundy_etal:2006; @Stott_etal:2007]); this phenomenon has become known as [*downsizing*]{} [@Cowie_etal:1999]. A number of key issues remain unresolved however. There are indications that the build up 