Question: How can the essence of a swarmer be described?
About the article "Boxing", section "Swarmer/in-fighter".

Candidate passages:
The "Caulobacter" stalked cell stage provides a fitness advantage by anchoring the cell to surfaces to form biofilms and or to exploit nutrient sources.
Generally, the bacterial species that divides fastest will be most effective at exploiting resources and effectively occupying ecological niches.
Yet, "Caulobacter" has the swarmer cell stage that results in slower population growth.
What is the offsetting fitness advantage of this motile cell stage?
The swarmer cell is thought to provide cell dispersal, so that the organism constantly seeks out new environments.
This may be particularly useful in severely nutrient-limited environments when the scant resources available can be depleted very quickly.
Many, perhaps most, of the swarmer daughter cells will not find a productive environment, but the obligate dispersal stage must increase the reproductive fitness of the species as a whole. 
 A well established example of bacterial aging is Caulerbacter "Crescentus".
This bacteria begins its life as a motile swarmer cell.
Once it has found a suitable substrate, the swarmer cell will differentiate into a non-motile stalked cell.
The stalked cell then becomes reproductively active and gives rise to new swarmer cells.
The number of progeny produced per hour by individual swarmer cells was shown to decrease with age.
This was the first evidence of bacterial aging. 
The life cycle of many planctomycetes involves alternation between sessile cells and flagellated swarmer cells.
The sessile cells bud to form the flagellated swarmer cells which swim for a while before settling down to attach and begin reproduction. 
 styles.
Definition of style.
"Style" is often defined as the strategic approach a fighter takes during a bout.
No two fighters' styles are alike, as it is determined by that individual's physical and mental attributes.
There are three main styles in boxing: out-fighter ("boxer"), brawler (or "slugger"), and In-fighter ("swarmer").
These styles may be divided into several special subgroups, such as counter puncher, etc.
The main philosophy of the styles is, that each style has an advantage over one, but disadvantage over the other one.
It follows the rock-paper-scissors scenario - boxer beats brawler, swarmer beats boxer, and brawler beats swarmer. 
In-fighters/swarmers (sometimes called "pressure fighters") attempt to stay close to an opponent, throwing intense flurries and combinations of hooks and uppercuts.
A successful in-fighter often needs a good "chin" because swarming usually involves being hit with many jabs before they can maneuver inside where they are more effective.
In-fighters operate best at close range because they are generally shorter and have less reach than their opponents and thus are more effective at a short distance where the longer arms of their opponents make punching awkward.
However, several fighters tall for their division have been relatively adept at in-fighting as well as out-fighting.
The essence of a swarmer is non-stop aggression.
Many short in-fighters utilize their stature to their advantage, employing a bob-and-weave defense by bending at the waist to slip underneath or to the sides of incoming punches.
Unlike blocking, causing an opponent to miss a punch disrupts his balance, permits forward movement past the opponent's extended arm and keeps the hands free to counter.
A distinct advantage that in-fighters have is when throwing uppercuts where they can channel their entire bodyweight behind the punch; Mike Tyson was famous for throwing devastating uppercuts.
Marvin Hagler was known for his hard "chin", punching power, body attack and the stalking of his opponents.
Some in-fighters, like Mike Tyson, have been known for being notoriously hard to hit.
The key to a swarmer is aggression, endurance, chin, and bobbing-and-weaving.
Notable in-fighters include Julio César Chávez, Miguel Cotto, Joe Frazier, Danny García, Mike Tyson, Manny Pacquiao, Saúl Álvarez, Rocky Marciano, Jack Dempsey, Wayne McCullough, Harry Greb, David Tua and Ricky Hatton.