for^R/for^R third instar larvae display a significantly longer travel path during feeding and reduced food intake compared to for^s/for^s larvae.

for^R homozygous larvae show significant increase in travel path length during feeding and food search compared to for^s homozygotes, while the path length of for^R/for^s transheterozygotes is not significantly different from for^R homozygotes. However, the food intake of for^R larvae is significantly lower than that of both for^s and for^R/for^s mutants. for⁰/for^R transheterozygotes display longer travel path and reduced food intake compared to for⁰/for^s.

for^R/for^s have a similar foraging success to flies homozygous for for^R which is significantly higher than for^s homozygotes.

Expressing for^{dsRNA.UAS.pr4} under the control of Scer\GAL4^da.PU in a for^R/for^s background has no effect on foraging success or distance travelled when compared to for^R/for^s controls.

The 'food leaving' behaviour score for for^R flies is low for flies raised in food-deprived conditions and high for flies raised in well-fed conditions. The increase in the score from food-deprived to well-fed is greater for for^R than for^s or for^s2 flies.

The increase seen in metabolite content of adult heads in for^R flies raised on food-deprived versus well-fed conditions is greater than for^s2 flies in the case of lipids, but less than for^s2 flies in the case of carbohydrates.

In well-fed conditions, adult for^R flies have almost twice as much energy stored in whole-body lipid and about half the energy stored in carbohydrates compared to adult for^s or for^s2 flies.

for^R flies exhibit greater food-related plasticity than for^s or for^s2 flies for a large majority of behavioural, metabolic and gene expression traits.

Homozygous for^R flies exhibit pattern memory that is not significantly different from that of wild-type controls. for^R/Df(2L)ed1 and for^R/for^s flies show impaired visual pattern memory.

Similarly to wild-type flies, homozygous for^R flies are able to recognise different patterns. The thermotolerance of homozygous for^R mutants is similar to that of wild-type flies.

Fifteen minutes after a single conditioning cycle or a spaced (five conditioning cycles separated by 20-minute intervals) protocol, for^R homozygous mutants show stronger avoidance of the odor previously associated with shock than for^s or for^s2 homozygous mutants .

24 hours after a spaced (five conditioning cycles separated by 20-minute intervals) protocol, the for^R homozygous mutants show weaker memory of the association between an odor and shock than for^s or for^s2 homozygous mutants.

24 hours after a massed (five conditioning cycles immediately after one another) protocol, there is no difference between for^R, for^s and for^s2 homozygous mutants.

In for^s homozygous mutants, expression of for^UAS.T2 under the control of either Scer\GAL4^30Y,

Scer\GAL4^c739 or Scer\GAL4^Tab2-201Y leads to higher fifteen-minute memory scores after a single conditioning cycle (similar to those observed in for^R homozygous mutants) and lower 24 hour memory scores after a spaced protocol (similar to or below those observed in for^R homozygous mutants) when compared to controls.

for^R adults are significantly more active compared to for^s adults in a locomotor activity assay.

A significant increase in capa-stimulated fluid transport is observed at 50 and 60 minutes in Malpighian tubules from for^s animals, compared to those from for^R animals. This difference is especially pronounced at 60 minutes. There is no difference in basal fluid transport rates between the two lines.

for^s flies show a more rapid response decrement of the long-latency giant fiber response induced by electrical stimulation than for^R flies. for^R/for^s flies show a rate of response decrement intermediate between that of for^s and that of for^R.

for^R and for^R/for^s flies show full recovery from decrement to five-failure criterion of the long-latency electrically induced giant fiber response after 5 seconds of rest.

for^R larvae do not show "scribbler" behaviour (significantly more turning behaviour than wild-type larvae) on non-nutritive agar.

In the giant neuron culture system neither spontaneous nerve firing nor supernumerary aftershock nerve spikes are evident. In voltage clamp experiments, for^s and for^s2 neurons show significantly lower levels of both peak and sustained outward currents compared with for^R. Half-activation voltages of the peak (but not sustained) K⁺ currents in for^s and for^s2 are shifted towards positive potentials compared with for^R. Slopes of voltage dependent activation are similar for the three alleles for both peak and sustained currents. Small amplitude (>0.5nA) spontaneous ejcs occur at low frequency (<2Hz). Motor terminal projections on the larval muscles are anatomically normal.

The initial response to 1% oxygen hypoxia, cessation of feeding and movement to the surface of the yeast, occurs similarly in for^R and for^s, though the for^s larvae move more slowly. However significantly fewer for^s than for^R (13% as opposed to 49%) go on the next phase of the behavioral response, migrating away from the yeast. While for^s embryos survive 12 hrs of hypoxia poorly, for^R embryos survive well. for^s larvae also recover less well from hypoxia than do for^R larvae. Hypoxia blocks BrdU incorporation in cultured CNS of for^R, but not for^s larvae. for^s embryos retain the ability to block S phase under hypoxia.

The olfactory response of homozygous for^R and homozygous for^s2 larvae to a food attractant is not significantly different. The number of homozygous for^s2 adult flies in an olfactory trap containing a food medium attractant after 48 hours is significantly greater than that of homozygous for^R adult flies. The increased olfactory trap response of for^s2 is recessive to the olfactory trap response of the for^R allele. The olfactory avoidance responses of for^R and for^s2 adult flies to propionic acid, ethyl acetate and acetone do not differ significantly.

for^R larvae show "rover-like" foraging behaviour. nob^KS49; for^R larvae show "sitter-like" foraging behaviour. for^R adults walk further from a recently ingested sucrose source than for^s2 flies. Csr³ does not increase walking distance in combination with either for allele.

Homozygous for^R larvae have longer crawling paths than homozygous for^s larvae, and are parisitised more often by A.tabida than homozygous for^s larvae. Homozygous third instar larvae have longer crawling paths than homozygous second instar larvae.

Larvae have longer locomotory trails than larvae for for^s.

Adults carrying the R allele walk farther from food source after feeding than do adults with the S strain. Unlike in larval tests, the rover behavior of adults is not dominant over the sitter behavior.

Larvae homozygous for the "sitter" alleles for^s or for^lsR92 move equally as well as larvae homozygous for the "rover" for^R allele on non-nutritive substrates. Larvae homozygous for the for^R allele take more strides, not longer ones, than larvae carrying for^s or for^lsR92 on foraging substrates.

rover allele

G9a^DD1, for^R has abnormal starvation stress response | female phenotype

for^R, lilli^189Y/lilli[+] has abnormal memory phenotype