In most cases, people survive better in numbers. The groups who survive normally assign a leader to the group. The leader of the group will organize and assign tasks to help keep each other alive and on task. This can be in a stationary setting or mobile setting while moving to survive some type of disaster such as an airplane crash or natural disaster. The objective is to keep each other alive.
How do you choose a leader? Some groups must choose a leader while in other cases one will emerge. The leadership position could be granted based on a persons position at the time a leader is needed. In a stationary setting the leader could be the property owner where it is an assumed role. In a mobile setting the leader could one who was in charge before the event started. The leader should consult with the group but also take responsibility for made decisions. The leader should bolster the emotional health of the group. In a survivor situation the leader and group will deal with all sorts of emotional issues most likely. Guilt, depression, resignations, anger, are just a few of the issues to be dealt with. Why am I alive and he/she is not? A leader will work to minimize panic and fear while contributing to a positive mental attitude. If you read Hope For Survival, I talk early in the book how my older sister instilled a positive attitude while we searched for food as kids. She was maybe 10 at the time but she showed no fear in our situation. The leader should monitor the members for signs of discourse and separation from the group. Every member should play a part in the survival efforts. A leader is good listener and won't hesitate making decisions after gathering the facts to base it on.
A group could have been friends for a long time or a group thrown together as strangers because of the event or disaster. A group who are friends and know each other before the event are more likely to work together and follow the leader at first. Circumstances creates stress which can often break members in to splinter groups within the group. This can be bad. Hunger, fear, being tired, hopelessness when things get no better are often ways the group will fragment apart. Another item I wrote about at length in the book is one's "mental" well being. How does a person handle adversity. Their own for that matter. If the group has been together for a while, it will hopefully have given the leader time to witness how each member handles stress. Put the group in an environment where they are wet, cold, and hungry and see how fast they melt down. The leader of the group of unknowns is much different. The leader does not know the people so he will have to use the same leadership skills above but monitor much closer.
Another situation could be where the group has no leader or a small group may believe the group is being poorly led. It may be a hard decision but you may be better off opting to go solo. It is not recommended but if you believe you have a better chance of surviving what you are facing doing it your way, then do it.
I will tell you a leader is not someone who read the book on Leadership. A leader has read the book but more so been in the field to practice and perfect what was read. Not all books are perfect and some must be adjusted to the event or scenario. I was blessed with good leaders in the military but not every leader was good. A good Sergeant once told me "if you are out in the field and the leader says "the book says we should" then run fast in the opposite direction. This may be your decision to make as well.