The descendants of the first quasars in the BlueTides simulation
  Supermassive blackholes with masses of a billion solar masses or more are
known to exist up to $z=7$. However, the present-day environments of the
descendants of first quasars is not well understood and it is not known if they
live in massive galaxy clusters or more isolated galaxies at $z=0$. We use a
dark matter-only realization (BTMassTracer) of the BlueTides cosmological
hydrodynamic simulation to study the halo properties of the descendants of the
most massive black holes at $z=8$. We find that the descendants of the quasars
with most massive black holes are not amongst the most massive halos. They
reside in halos of with group-like ($\sim 10^{14}M_{\odot}$) masses, while the
most massive halos in the simulations are rich clusters with masses $\sim
10^{15} M_{\odot}$. The distribution of halo masses at low redshift is similar
to that of the descendants of least massive black holes, for a similar range of
halo masses at $z=8$, which indicates that they are likely to exist in similar
environments. By tracing back to the $z = 8$ progenitors of the most massive
(cluster sized) halos at $z=0$; we find that their most likely black hole mass
is less than $10^7 M_{\odot}$; they are clearly not amongst the most massive
black holes. We also provide estimates for the likelihood of finding a high
redshift quasar hosting a black hole with masses above $10^{7} M_{\odot}$ for a
given halo mass at $z=0$. For halos above $10^{15} M_{\odot}$, there is only
$20 \%$ probability that their $z=8$ progenitors hosted a black hole with mass
above $10^{7} M_{\odot}$.
