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Differences in the amount of time spent on foraging on different patches compared between wild and domesticated pigs.
After Gustafsson et al., 1999.

Gustafsson et al.’s data support their hypotheses. Domestic and crossbred pigs’ behavior followed optimal foraging theory. Both groups spent less time in patches with less food and visited fewer patches when there was a cost to move to a different patch. As predicted, the crossbred pigs used a costlier foraging strategy by moving between patches more frequently than the domestic pigs ( [link] ).

The finding that domesticated animals use a less costly foraging strategy than wild ones is not limited to pigs—for example, it has been found in comparisons of domesticated and crossbred chickens (Andersson, 2001; Schutz, 2000)—and may be characteristic of the domestication process (Jensen and Gustafsson, 1997).

What is the relationship between domestication and natural selection?

Domestication is the process by which animals adapt to humans and their environment (Price, 1984). The main feature of domestication that separates it from taming is that for domestication to occur, humans must control which individuals reproduce (Mignon-Grasteau et al., 2005). This process, in which humans select for desired traits and may produce new breeds, is called artificial selection.

Resource allocation theory argues that an animal’s resources are balanced between traits for breeding and production (Mignon-Grasteau et al., 2005). Thus, when humans select for a particular trait, there will be a decrease in another trait unless the animal’s resources increase. As a consequence of this, humans selecting for one trait may unintentionally change an unrelated trait.

For some traits, the pressures of artificial selection and natural selection may bring about the same result. For example, both natural and artificial pressures favor large pigs. Traits for self-defense or predatory behavior are not selected by humans, and often decrease or are lost in the process of domestication (Mignon-Grasteau et al., 2005). For instance, natural selection has resulted in wild boars with long, sharp tusks while selective breeding has resulted in domestic pigs with less conspicuous tusks.

How do pigs interact when foraging?

Wild and domestic pigs are highly social animals (Grandin, 2009, Graves 1984). As piglets, they fight viciously over their mother’s teats before setting up a hierarchy that determines which sibling receives the most milk (Fraser, 1991; Fig. 4).. Even after they are weaned, pigs’ feeding behavior is complex and rarely solitary. Social foraging theory is used to study these types of interactions, in which one forager’s actions affect another’s (Giraldeau and Caraco, 2000). Social foraging theory and optimal foraging theory are not competing theories. Optimal foraging theory predicts the behavior of individual foragers while social foraging theory predicts the behavior of foragers in groups.

Adult pigs also establish dominance hierarchies that help quell competition for food (Nielsen, 1996), but this does not mean that aggression motivated by food resources disappears entirely. Wild boars fight more often in the winter when food is scarce than in the summer when it is more plentiful (Graves, 1984). Thomsen et al. hypothesized that this may be due to the spatial distribution of food as well as its availability (Thomsen et al., 2010). They predicted that the number of aggressive interactions between domestic pigs would increase when buckets of food were clustered together versus spread out to a medium or far distance from each other, even if the total amount of food were the same in each condition. As shown in [link] , this hypothesis was supported.

Questions & Answers

anyone know any internet site where one can find nanotechnology papers?
Damian Reply
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
many many of nanotubes
what is the k.e before it land
what is the function of carbon nanotubes?
I'm interested in nanotube
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
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Source:  OpenStax, Mockingbird tales: readings in animal behavior. OpenStax CNX. Jan 12, 2011 Download for free at http://cnx.org/content/col11211/1.5
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