Simulated annealing and MCMC analyses require a random number to seed the chain. MARK will get a random starting value from the date and time on your machine if you do not enter a value. However, a feature has been added that contacts the Australian National University web site to retrieve a string of random numbers using the wget command. I've noticed that wget often fails if you have not recently opened the web site. The following URL will open the site and show 8 random integers:
https://qrng.anu.edu.au/API/jsonI.php?l ... ype=uint16
If wget is failing to produce values on your runs, open this site and try again.