PHOTOTAXIS IN DROSOPHILA INFANT LOOKING BEHAVIOUR

1. INDIRA GANDHI COLLEGE
OF ARTS AND SCIENCE
NELLIKUZHI
(AFFILIATED TO MAHATMA GANDHI UNIVERSITY)
MSC ZOOLOGY - FIRST SEMESTER
MINI PROJECT REPORT
NAME: ANU VARGHESE
REG.NO: 210011016602

2. BEHAVIOURAL
STUDY

3. PHOTOTAXIS
IN DROSOPHILA

4. CONTENT
SERIAL
NO
CONTENT PAGE NO
1 AIM AND OBJECTIVE 2
2 INTRODUCTION 3-4
3 REVIEW OF LITERATURE 5
4 METHODOLOGY 6
5 OBSERVATION 7-8
6 RESULT 9
7 CONCLUSION 10
8 REFERENCE 11

5. AIM AND OBJECTIVE
 To study the photo taxis behavior in drosophila.
 To study about the movement of drosophila with
respect to the light.
 To find out whether the drosophila shows either
positive or negative phototaxis.

6. INTRODUCTION
Drosophila melanogaster is a species of fly (the taxonomic order Diptera) in the
family Drosophilidae. Drosophila melanogaster remains one of the most
commonly used model organisms for biomedical science. The species is often
referred to as the fruit fly or lesser fruit fly, or less commonly the "vinegar fly" or
"pomace fly". D. melanogaster is typically used in research owing to its rapid life
cycle, relatively simple genetics with only four pairs of chromosomes, and large
number of offspring per generation.
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Diptera
Family: Drosophilidae
Genus: Drosophila
Species: melanogaster
It is small in size, short generation time and large brood size make it ideal for
genetic studies. They exhibit sexual dimorphism; females are about 2.5 mm long
while males are slightly smaller with darker backs. Drosophila melanogaster lives
in a wide range of habitats. Native habitats include those in the tropical regions of
the Old World, but the common fruit fly has been introduced to almost all
temperate regions of the world. Drosophila mature through complete
metamorphosis.

7. The behavior of Drosophila melanogater is simplistic. They are easily drawn
towards the smell of any food source, and will mate almost indiscriminately with
any individual of the opposite sex. They have hairs on their backs that are sensitive
to air currents; their eyes are sensitive to slight differences in light intensity; and
they will instinctively fly away when they sense a shadow or movement.
The fruitfly is behaviourally active twice a day ie; in the morning and evening.
They mostly prefers reactively cooler climate and hence are most active during
dawn and desk.
The behavioral responses of adult Drosophila to a variety of sensory stimuli
includes light, volatile and non-volatile chemicals, temperature, humidity, gravity,
and sound. Organisms respond behaviorally to various stimuli in their
environment: for example, light, chemicals, temperature, humidity, gravity, and
sound. The sensing of these stimuli is carried out, respectively, by vision, smell of
volatile chemicals (olfaction), taste of nonvolatile chemicals (gustation), thermo
sensors, humidity sensors, gravity sensors, and hearing. The responses to stimuli
can be attraction or repulsion, depending on the nature and the intensity of the
stimulus.
There are two types of taxis under study phototaxis and geotaxis. Geotaxis is the
organism move in accordance with gravity. Phototaxis is the ability of organisms
to move directionally in response to a light source. Most animals readily react in
light. If the movement is towards light, it is known as positive phototaxis while if it
move away from light it is said to be negative phototaxis.
Phototaxis in Drosophila is a robust behavior that has been used since the earliest
genetic screens to study photoreceptor function in vision. Drosophila melanogaster
also have a propensity to fly towards light. If you culture the flies in a tube it is
easily noticable that the flies will migrate towards the side of the tube that is
nearest to the brightest source of light.

8. REVIEW OF LITERATURE
There are many research related to the phototaxic behavior of drosophila some of
them are listed below:
Hirsch and Boudrean (1958) applied the technique in studying the heritability of
phototaxin in drosophila. In this experiment a population of drosophila is screened
by exposing each individual to a light dark choice as it passed through a Y tube.
Each individual is tested 10 times and selection pressure is applied through
associative mating to produce strains varying in their characteristic degree of
positive phototaxis.
Julia Johnson, Ari Neveres and Rikul Thapar studies on the effects of light on the
phototaxic behavior of drosophila. In this experiment, fruit flies are kept in glass
container and experiment continues with differ colour of light. They found out that
drosophila perforn positive phototaxis.
Research conducted by Jamey S. Kain, Chris Stokes, and Benjamin L. de Bivort
(2012) studied the topic on Phototactic personality in fruit flies and its suppression
by serotonin and white. Using genetics and pharmacology, we identify the
metabolite transporter White and white-dependent serotonin as the suppressors of
phototactic personality.
Nortin M Hadler studied the topic on the genetic influence of phototaxis in
Drosophila melanogaster. The interaction of the environmental and genetic
influence on phototactic behavior in fruit fly is demonstrated in this experiment.
Drosophila melanogaster was the organism chosen by earlier workers for the
investigation of individual differences and analysis of the genetic contribution of
observed behavior.

9. METHODOLOGY
This project is mainly based on primary data. The experiment is
conducted at home. It is conducted around 1 week from 10th
April to 17th
April. A few number of fruit fly is collected in a jar and place a lid on
the top of the jar so that no drosophila can enter out of the jar.
Materials required in this experiment includes jar, drosophila, black
paper and a light source. This project is conducted based on the primary
available data.
Firstly, collect the required drosophila and introduce it in a jar. The
mouth of the jar is closed in order to avoid exit of the flies.
Secondly, a black paper of 4 cm length and 4 cm width is taken and
cover one side of the jar with this black paper. Then take a black paper
of 6cm length and 6 cm width is taken and cover the jar. The experiment
setup is placed on a table and place the light source and observe the
movement of flies. The movement of flies are observed for a week.

10. OBSERVATIONS
Date: 10-04-2022 TO 17-04-2022
STEPS METHODS OBSERVATIONS
1
In the first step, fruit flies are
spread all over the jar, as the light
is penetrating from all the
directions.
2
A black paper (4x4 cm) is placed
on one side of the jar. It can be
seen that the fruit flies move
towards the area where there is
light.
3
A black paper of 6x6 cm) is placed
on the jar. We could see that the
flies get concentrated in the region
where a small amount of light is
reached.
One week observation is made in this study. All these days the
observation regarding the movement of fruit fly towards light is
same as such. Thus we can conclude that drosophila is showing
a phototaxic behavior.

11. GRAPHICAL REPRESENTATION
Intensity of darkness is directly proportional to the
movement of fruit flies towards lighted portion.
Movement of fruit flies towards lighted portion
Intensity of
darkness
X AXIS
Y AXIS

12. RESULT
All the fruit flies move towards the uncovered area as
there is a little amount of light source. Thus we can
conclude that Drosophila melanogaster is showing
positive phototaxis.

13. CONCLUSION
Phototaxis in drosophila is a robust behavior. Phototaxis is one of the
form of taxis. Phototaxis is the ability of organisms to move
directionally in response to a light source. Most animals readily react in
light. If the movement is towards light, it is known as positive phototaxis
while if it move away from light it is said to be negative phototaxis.
In our study we take the Drosophila for observing the phototaxic
behavior. We had taken a jar with few fruit flies in it. Firstly the jar is
covered with a small black paper. We could see that the fruit flies are
located in the light penetrating region. Then a large black paper is
placed. As the large area is covered by black paper only few light had
entered into the jar. The flies are concentrated towards the light source
area than the other side. Thus we can conclude that drosophila is
showing a positive phototaxic behavior.

14. REFERENCE
1. Jamey S. Kain, Chris Stokes, and Benjamin L. de Bivort
(2012) “Phototactic personality in fruit flies and its
suppression by serotonin and white”
2. Julia Johnson, Ari Neveres and Rikul Thapar (2016)
“Articles on the effects of different light intensities on the
phototaxis response of Drosophila melanogaster”

15. INFANT LOOKING TIME
HABITUATION

16. CONTENT
SERIAL NO CONTENT PAGE NO
1 AIM AND OBJECTIVE 3
2 INTRODUCTION 4
3 REVIEW OF LITERATURE 5
4 METHODOLOGY 6
5 OBSERVATION AND
RESULT
7-9
6 CONCLUSION 10
7 REFERENCE 11

17. AIM AND OBJECTIVE
 To study about the early infants memory habituation.
 To compare the memory habituation of infants of two
different age group.
 To understand the time taken to respond to a particular
stimulus.

18. INTRODUCTION
Visual recognition memory is a robust form of memory that is evident from early
infancy. From birth, babies begin exploring the wonders in the world with their
eyes. Even before they learn to reach and grab with their hands or crawl and sit-up,
their eyes are providing information and stimulation important for their
development. Eye and vision problems in infants can cause developmental delays.
By 10 months, babies remember several things, their short term memory develops
extremely rapidly in the first year of life. In general, short-term memory emerges
early in life, it rapidly develops between 4 and 10 months of age. For visual
exploration to fuel early learning and development, eye movements must be
selective; that is, they must reliably be directed to events and objects that are
currently relevant.
Short-term memory is the kind of memory we use when we recognize that an
object that is briefly out of sight is the same when it reappears—for example
recognizing that a ball that rolls under the couch is the same ball that emerges from
the other side (at least if it’s the same color, shape, and size). This kind of memory
is critical to see the visual world as unchanging as we blink and move our eyes
around. This kind of memory is important for babies.
In general, we have discovered that although short-term memory emerges early in
life, it rapidly develops between 4 and 10 months of age. These early limits on
short-term memory might be especially important for helping young babies deal
with the overwhelming amount of new information they encounter each day.
Typically, infants looking time decreases with repeated exposure to the stimulus
and it increases to novel items. When similar thing is detected their looking time
decreases. When differences are detected their looking time increases.

19. REVIEW OF LITERATURE
There are many research related to the habituation of infant to a
particular stimulus. some of them are listed below:
Brennan, Ames and Moore (1966), Coben (1972), Mc call and Kegan (1967),
Thosmas (1965). They conclude that habituation is influenced by factors such as
stimulus, complexity, gender and infant age.
Fagan (1970), Saayman, Ames and Moffatt (1964). They studied about the
habituation of looking time. Infants in the age range from 3 to 9 months
demonstrated differential fixation time to novel and familiar targets. Their work
revealed that infants look to the stimulus that are novel.
Fantz RL. Visual experience in infants: decreased attention to familiar patterns
relative to novel ones. This indicated the occurrence of recognition and habituation
of visual responsiveness to specific patterns, and suggested that familiarization
with the environment begins through visual exploration before more active
exploration is possible.
Rose S A, Feldman J F, & Jankowski JJ (2004) ‘Infant visual recognition
memory’. Infant visual recognition memory shows modest reliability, good
discriminant validity, good predictive validity, and significant cross-age continuity.
Infant visual recognition memory is related to, and may be to some extent
accounted for by, processing speed, forgetting, and certain aspects of attention
(particularly look duration and shift rate). There is growing evidence that infant
recognition memory may be an early form of declarative memory that depends on
structures in the medial temporal lobe.

20. METHODOLOGY
The present study is mainly based on primary data. It is conducted
at home, around one month from 13th
April to 5th
june. Infant
looking habituation is observed in two different month of the child
in this experiment ie; at five month old and at 8 month old. In both
cases same methodology is used.
Date of the experiment: 19 march 2022 to 12 may 2022
STEP 1: In the first step, the five month old baby is placed on the
bed or chair. The colored toy is shown in front of the baby and
then start the stop watch. Note the distraction of eye of the baby
and suddenly stop the stop watch and note the observations. Repeat
it for some time and record the readings
STEP 2: In the second step, the eight month old baby is placed on
the bed or chair and the same colored toy is shown in front of the
baby and then start the stop watch. Note the distraction of eye of
the baby and suddenly stop the stop watch and note the
observations correctly. Repeat it for some time and record the
readings

21. OBSERVATION AND RESULT
Date: 13-04-2022 to 5 -05-2022
Looking time habituation of five month old baby
REPETITION NUMBER LOOKING TIME(sec)
FIRST 43.55
SECOND 22.23
THIRD 10.92
FOURTH 6.00
FIFTH 3.73
SIXTH 1.89
GRAPHICAL REPRESENTATION
0
5
10
15
20
25
30
35
40
45
50
FIRST SECOND THIRD FOURTH FIFTH SIXTH
LOOKING
TIME
REPETITIONNUMBER
5 MONTH OLD BABY

22. LOOKING TIME HABITUATION OF EIGHT MONTH OLD BABY
REPETITION TIME LOOKING TIME
FIRST 19.28
SECOND 14.55
THIRD 9.43
FOURTH 4.86
FIFTH 1.86
SIXTH 1.21
GRAPHICAL REPRESENTATION
0
5
10
15
20
25
FIRST SECOND THIRD FOURTH FIFTH SIXTH
LOOKING
TIME
REPETITIONNUMBER
EIGHT MONTH OLD BABY

23. COMBINED GRAPH
Infants looking time habituation is noted from this graph. The
graph showing different age group infants. In five month old baby
the intelligent power is less as compared to the eight month old
baby. The five month old baby looks more time to the object
shown but it seems to be less in eight month old child. The
memory power of infants increases with the age.
0
5
10
15
20
25
30
35
40
45
FIRST SECOND THIRD FOURTH FIFTH SIXTH
Series 1 43.55 22.23 10.92 6 3.73 1.89
Series 2 19.28 14.55 9.43 4.86 1.86 1.21
LOOKING
TIME
REPETITIONNUMBER
LOOKING TIME OF INFANTS
Series 1 Series 2

24. CONCLUSION
Looking time habituation is noted in this study. In five month old
baby the intelligent power is less and looks more time to the object
as compared to the eight month old baby. The memory power of
infants increases with the age. Habituation of looking time is a
powerful tool that can be used to study a wide range of area across
the entire period of infancy. It is the common behavioral technique
their by we can examine logic, utility and future aspects.

25. REFERENCES
1. Bahrick L E, Pickens J N (1995). Infant memory for object
motion across the period of three months; journal of
experimental and psychology. Special issue: early memory;
59:343-371
2. Colombo J & Mitchell D W(1999). Infant visual habituation.
Neurobiology of learning and memory in press.
3. Fagan JF (1970) Memory in the infant. Journal of
experimental child psychology, 9:217-226
4. Miller DJ (1972) visual habituation in human infant. Child
development, 43:481-493.
5. Thomas H & Gilmore R O (2004). Habituation assessment in
infancy. Psychological methods, 9, 70-92.