  The MANIFEST fibre system provides a highly versatile feed for the GMACS and
G-CLEF first-light spectrographs on the Giant Magellan Telescope (GMT).
Combining these low- and high-resolution optical spectrographs with the wide
field of view (up to 20 arcmin), high multiplex, and integral field
capabilities provided by MANIFEST enables science programs that are not
achievable with other extremely large telescopes. For galactic archaeology and
near-field cosmology studies of Local Group galaxies, MANIFEST and G-CLEF can
obtain up to 40 simultaneous high-resolution optical spectra over a wide field,
and so produce detailed kinematic and chemical maps of the stellar populations
out to large radius in galaxies covering a broad range of masses and
morphologies. For galaxy evolution studies, MANIFEST and GMACS can combine a
survey of galaxies at the epoch of peak star formation with a study of the
flows of gas between galaxies and the circumgalactic medium, mapping both the
emission from hot gas using integral field spectroscopy and the absorption from
cold gas with multi-object spectroscopy of background sources. These programs
will feature strongly in the early science goals for GMT.
