It's not that complex. The crows were using(defined below) a tool (defined below) to get food (a particular function).

tool
to͞ol/
noun
noun: tool; plural noun: tools

1.
a device or implement, especially one held in the hand, used to carry out a particular function.
"gardening tools"
synonyms:	implement, utensil, instrument, device, apparatus, gadget, appliance, machine, contrivance, contraption; informalgizmo
"garden tools"
a thing used in an occupation or pursuit.
"computers are an essential tool"
a person used or exploited by another.
"the beautiful Estella is Miss Havisham's tool"
synonyms:	puppet, pawn, creature, cat's paw; More
minion, lackey, instrument, organ;
informalstooge
"the beautiful Estella is Miss Havisham's tool"
Computing
a piece of software that carries out a particular function, typically creating or modifying another program.
2.
a distinct design in the tooling of a book.
a small stamp or roller used to make a tooled design.
3.
vulgar slang
a man's penis.
a stupid, irritating, or contemptible man.
"that guy is such a tool"

verb
verb: tool; 3rd person present: tools; past tense: tooled; past participle: tooled; gerund or present participle: tooling

1.
impress a design on (leather, especially a leather book cover).
"volumes bound in green leather and tooled in gold"
dress (stone) with a chisel.
synonyms:	work, fashion, shape, cut; More
ornament, embellish, decorate, chase
"tool leather into a saddle"
2.
equip or be equipped with tools for industrial production.
"the factory must be tooled to produce the models"
3.
North Americaninformal
drive or ride in a casual or leisurely manner.
"tooling around town in a pink Rolls-Royce"

Search Results
use
verb
verb: use; 3rd person present: uses; past tense: used; past participle: used; gerund or present participle: using

1.
take, hold, or deploy (something) as a means of accomplishing a purpose or achieving a result; employ.
"she used her key to open the front door"
synonyms:	utilize, make use of, avail oneself of, employ, work, operate, wield, ply, apply, maneuver, manipulate, put to use, put/press into service More
"she used her key to open the front door"
exercise, employ, bring into play, practice, apply, exert, bring to bear
"the court will use its discretion in making an order"
take or consume (an amount) from a limited supply of something.
"we have used all the available funds"
exploit (a person or situation) for one's own advantage.
"I couldn't help feeling that she was using me"
synonyms:	take advantage of, exploit, manipulate, take liberties with, impose on, abuse; More
capitalize on, profit from, trade on, milk;
informalwalk all over
"he just felt used"
treat (someone) in a particular way.
"use your troops well and they will not let you down"
apply (a name or title) to oneself.
"she still used her maiden name professionally"
informal
one would like or benefit from.
"I could use another cup of coffee"
informal
take (an illegal drug).
"they were using heroin daily"
2.
describing an action or state of affairs that was done repeatedly or existed for a period in the past.
"this road used to be a dirt track"
3.
be or become familiar with someone or something through experience.
"she was used to getting what she wanted"

noun
noun: use
yo͞os/

1.
the action of using something or the state of being used for some purpose.
"a member of staff is present when the pool is in use"
synonyms:	utilization, usage, application, employment, operation, manipulation
"the use of such weapons"
the ability or power to exercise or manipulate something, especially one's mind or body.
"the horse lost the use of his hind legs"
a purpose for or way in which something can be used.
plural noun: uses
"the herb has various culinary uses"
synonyms:	need, necessity, call, demand, requirement
"composers have not found much use for the device"
the value or advantage of something.
"it was no use trying to persuade her"
synonyms:	advantage, benefit, service, utility, usefulness, help, good, gain, avail, profit, value, worth, point, object, purpose, sense, reason
"what is the use of that?"
Lawhistorical
the benefit or profit of lands, especially lands that are in the possession of another who holds them solely for the beneficiary.
the characteristic ritual and liturgy of a church or diocese.
the action of taking or habitual consumption of a drug.