Butterflies in Space Research Project 11th D class Coordinating teacher: Ioana Stoica “Tudor Vianu” National High School of Computer Science, Bucharest, Romania

Introduction Microgravity is a mystery we all wish to unravel – and this can only be done with experiments and careful observations. The goal of this research project is to study the behavior of monarch butterflies (Vanessa Cardui) in a laboratory environment, at constant pressure and temperature, and to compare the results with the data offered by NASA regarding the life of butterflies in microgravity. As an aside, in the end we came up with a term of endearment for our butterflies, naming them Vianuessa Cardui, because the name of our school is Tudor Vianu. The essay is structured in several parts. First, in order to choose our research questions, we studied the effects gravity has on living organisms and of those considered the aspects we were able to monitor by photos and videos. Then, we made some suppositions on how butterflies would behave under the effect of microgravity and how would the lack of gravitational force affect their biological processes. Also, we compared the actual experimental data collected by us with the data offered by NASA and verified our suppositions. Finally, we stated the conclusions of our research and suggested several enhancements and future studies.

How would the world look without gravity? The effects of gravity on living creatures, based on scientific studies, and their consequences in microgravity: 1. Cell size - Gravity: The size of single biological cells is inversely proportional to the strength of the gravitational field exerted on the cell. That is, in stronger gravitational fields the size of cells decreases, and in weaker gravitational fields the size of cells increases. Gravity is thus a limiting factor in the growth of individual cells [1]. - Microgravity: This suggests that organisms in microgravity might develop larger cells and thus, have larger size.

2. Inner/outer skeleton - Gravity: Organisms evolving on Earth must develop inner or outer skeletons for not being crushed by the gravitational force [2]. - Microgravity: Bone cells (or exoskeleton cells in case of insects) die if they can’t attach themselves to something. Without gravity exerting a downward pull on these bone cells, they float aimlessly about and eventually perish.

3. Blood circulation - Gravity: The vascular system must work against gravity in order for the blood to reach the parts of the body that are higher than the pump (the heart). - Microgravity: It’s possible that the lower parts of the body would receive less blood, while the upper ones will receive more, making some actions harder to perform and others easier. For example, a butterfly’s wings may be better vascularized in microgravity since they are situated in the upper part of the body [3].

What can we measure and observe through photographs and videos? Photographs

Videos

-

body shape and structure the size colors life cycle

-

flight patterns vitality (how active the butterflies are)

Research Questions and Hypotheses 1. Do the butterflies go through the metamorphosis stages normally? Hypothesis: Gravity influences a lot of functions in the living organisms and its absence can have an effect over a larva’s growing process. Therefore the caterpillar might transform slower into a pupa, while it could also spend more time in the pupa form. The butterfly might need more time to fully inflate its wings (because of the effect of microgravity on its blood circulation) and to dry them. Methods: We will watch the photos taken by the camera on the ISS and measure the time needed for the larvae to turn into pupa and for the pupa to turn into butterfly and see if it takes more or less time.

2. Does microgravity affect their movement pattern? Hypothesis: Microgravity might influence the butterflies’ speed (they can achieve greater speeds with far less effort) and cause muscle atrophy. We presume they will have issues maintaining their balance, will be disorientated and move erratically. Also, they might become lazier. Methods: We will analyze the videos from the ISS and try to find a pattern for the butterfly’s flight and if such a pattern exists, we will compare it to the movement patterns seen on Earth.

3. Do they have differences in structure or appearance? Hypothesis: The larvae on the ISS might be larger than those on Earth because their cells could be larger in microgravity. The exoskeleton in all stages of metamorphosis (caterpillar, pupa and butterfly) might also be slightly thinner because the cells forming this type of tissue develop much slower in microgravity. Also, the butterflies’ wings might remain a little wrinkled because the low gravity affects the blood flow that is pumped for inflating them. Methods: We will measure the size of the butterflies and larvae in the box on the ISS (from pictures) and compare them to the size of our insects. The “butterflynauts” may well be larger, but also smaller in size.

Experimental data I. Measurements 1. Methods applied: -

we took pictures of our butterflies everyday at 11 a.m. and compared them with the images from the ISS;

-

we made sketches of the butterflies to compare their physical features;

-

we monitored the pressure and temperature levels using the same barometer and thermometer each day, to make sure there were no fluctuations;

-

we measured the size of the larvae and butterflies, using a ruler;

-

we used mathematical equations to interpret the obtained data.

2. Sketches

Butterflies on Earth

Butterflies on the ISS

3. a) Day

11 (16.03.2010)

12 (17.03.2010)

13 (18.03.2010)

14 (19.03.2010)

15 (20.03.2010)

16 (21.03.2010)

Data tables: On Earth: Size Temperature Pressure (cm) (C) (mbarr)

3.8

4

4.4

4.4

4.4

4.4

22

23

23

23

23

23

Observations

1017

First day of measurements. Due to unfavorable weather conditions, we only have 4 larvae, instead of 5.

1017

The larvae get used with the new environment and start to build a wire network.

1017

The network becomes more complex; the food level decreases.

1017

The necessary amount of food has been consumed; the larvae become inactive.

1017

The larvae used the network to attach to the lid; they gradually come into the “J” position.

1017

The larvae are being moved to a bigger habitat.

Photo

b)

On the ISS: Day

Size (cm)

Temperature (C)

Pressure (mbarr)

10 (18.11.2009)

1.7

25

1013,25

11 (19.11.2009)

2.2

25

1013,25

12 (20.11.2009)

2.8

25

1013,25

13 (22.11.2009)

3.3

25

1013,25

14 (23.11.2009)

3.5

25

1013,25

15

3.6

25

1013,25

(24.11.2009)

Photo

4. Data processing a) Habitat conditions We registered only minor fluctuations of pressure and temperature in our research laboratory. Moreover, the measured values were in the accepted limits, similar to those on the ISS. Thus, these conditions shouldn’t have a significant influence on the butterflies’ behavior and development.

b) Butterfly size: The graph in Figure 1 illustrates a comparison between the sizes of the larvae on Earth and those on the ISS. We noticed that caterpillars on the ISS are smaller than ours, but they keep growing in length for all 6 days, while the ones we measured in the laboratory stopped growing in length after the first 3 days of measuring. 5,00 4,50 4,00 3,50 3,00 Earth

2,50

ISS

2,00 1,50 1,00 0,50 0,00 Day 1

Day 2

Day 3

Day 4

Day 5

Day 6

Figure 1: Representation of daily sizes for the larvae on Earth and on the ISS

c) Growth rate: We calculated the growth rate of the caterpillars as the arithmetic mean of the slopes of the lines forming the graph: -

Growth rate for our research butterflies: (0.2+0.4+0+0+0)/6 = 0.12;

-

Growth rate for the butterflies on ISS: (0.5+0.6+0.5+0.2+0.1) = 0.38.

Notice the value is greater for the “butterflynauts”.

d) Life cycle: Vianuessa Cardui

Butterflynauts

(research butterflies)

Caterpillar Chrysalis

13 days 11 days

Vanessa Cardui (general information)

6-7 days 7-8 days

7-11 days 7-11 days

Notice the butterflies in space evolve faster than the ones raised in our laboratory. [9]

II. Observations a) On the ISS: We analyzed the available footage which captured the butterflies’ behavior. The moments recorded were from two consecutive days: December 3, 2009: there is only one butterfly emerged from the pupa; -

December 4, 2009: a second butterfly emerges from the pupa.

Here are our observations below:

12/03/09: -

the butterfly is floating aimlessly inside the box;

------------------it does some short, sudden moves trying to control its direction, but doesn’t seem to have a target; it’s moving its body rather than its wings;

12/04/09: -

the elder butterfly (1 day old) is moving very slowly;

the newly-emerged butterfly looks disorientated and is desperately trying to stretch its wings; -------------------

the butterflies have problems maintaining their balance;

they are trying to attach themselves to the walls (not flying aimlessly anymore); there are some flying attempts, but they can’t control their speed and they keep hitting the walls; while one of the butterflies is more active (uses its wings often and tries to fly), the other one is static and moves using mainly its limbs.

b) On Earth: On Earth, Vanessa Cardui butterflies fly in a smooth, balanced way with a constant beat stroke of about 20 Hz assuring enough lift for a straight, horizontal flight. The monarch butterflies are capable of flying many miles in their lengthy migrations over North America and some of them even cross parts of the Atlantic. The length of these journeys exceeds the normal lifespan of most monarchs and only the fourth generation of butterflies completes them [4],[5],[6].

III. Error sources While analyzing and interpreting our data, we must also consider possible error sources: • Imperfections of the instruments used (rulers, thermometers etc.); • Gradients of temperature and pressure in our laboratory; • Disturbance of the butterflies’ activities by human presence (although we tried not to influence them in any way); • Approximation of the results; • Small number of studied butterflies.

Conclusions Considering the small number of Painted Lady butterflies studied in our laboratory, a generalization would be somewhat inappropriate. We tried, wherever possible, to compare our data with general characteristics for the Vanessa Cardui species and, unfortunately, we noticed several differences. However, some conclusions can still be inferred. We’ve noted our observations below, for each of the proposed research questions:

1. Do the butterflies go through the metamorphosis stages normally? The butterflies on the ISS seem to evolve slightly faster than the ones on Earth. Also, while in their caterpillar stage, they continue to grow for the entire period, while our research butterflies stagnate to a constant value after the third day.

2. Does microgravity affect their movement pattern? Monarchs on the ISS exhibit fairly modest flying attempts. Immediately after emerging from the pupa and drying their wings, the Vanessa Cardui butterflies try to use their wings for movement. The videos recorded on the ISS show that initially they are disoriented and cannot control their speed properly. However, they shortly adapt their behavior to the environment and omit using their wings extensively. Also, after periods of merely floating in microgravity, the butterflies seem to attempt to control their direction with sudden twists of the abdomen. On the other hand, the butterflies in our laboratory seemed disoriented immediately after emerging, but this was only a temporary state, as they soon started enhancing their flying skills. Also, Earth-raised butterflies seemed to be more active than the ISS-raised ones. In general, Vanessa Cardui butterflies on Earth fly in a balanced manner, a sign that they evolved on the planet from generation to generation. They migrate over large distances in different periods of the year, flying hundreds of miles in a controlled manner, which the butterflies on the ISS would certainly not be capable of [7],[8].

3. Do they have differences in structure or appearance? Our initial hypothesis was that the butterflies living in microgravity would be larger than the ones on Earth. This proved to be wrong. On the contrary, the “butterflynauts” are smaller in size than our butterflies – the caterpillars

differ with over 1 cm in length. We believe that butterflies born and raised in microgravity might grow to be larger because their cells would expand constantly and there wouldn’t be any accommodation period. However, the wingspan of the butterflynauts is approximately 5.5 cm, slightly larger than the average values for Vanessa Cardui. [4] Also, another difference we observed is that the wings of the “butterflynauts“ remain slightly wrinkled, probably due to the effect of microgravity.

Questions and Proposals for Further Study - How would butterflies born on the ISS behave on Earth? Would they survive? - Would butterflies born on the ISS, in microgravity conditions, grow bigger than the current “butterflynauts”? - Have any changes been observed in the behavior of the butterflies after returning from the ISS? If so, are the effects similar to those experienced by human astronauts? (e.g. dizziness etc) - Would a larger box (and perhaps fitted with a cleaning system to eliminate the frass and food residue) allow a better study of the flight patterns? Perhaps a larger box would let the butterflies actually fly, not just float in microgravity?

Acknowledgements Our sincere gratitude goes to everyone at NASA and BioEd for giving us the chance to take part in such an amazing project and to feel, even if only for a short while, like true scientists. Also, many thanks are due to Tim and Margaret Jenkins, at Gribblybugs, for sending us the caterpillars all the way from Coventry, England, despite the harsh weather conditions. [10]

Bibliography and Resources [1]. http://en.wikipedia.org/wiki/Gravitational_biology [2]. http://library.thinkquest.org/C003763/print.php?page=human03 [3]. http://astrobiology.nasa.gov/ask-an-astrobiologist/question/?id=761 [4]. Opler, P. A., and Wright, A. B., 1999. Peterson field guide to western butterflies. Houghton Mifflin Co., Boston. 544 pp. [5]. http://monarchwatch.smugmug.com/Monarchs-in-Space/Monarchs-onEarth/10367121_hyZuM#735342687_AiVnt [6]. http://monarchwatch.smugmug.com/Monarchs-in-Space/Monarchs-on-theSpace-Station/10305636_wwEsm#735343086_WAPzr [7]. http://en.wikipedia.org/wiki/Monarch_%28butterfly%29 [8]. http://www.monarch-butterfly.com/ [9]. http://www.monarchbutterflyusa.com/Cycle.htm [10].

www.gribblybugs.com

Photooos! Our stars, the Vianuessa Cardui!

Us!

Verifying the laboratory conditions (the flowers insure increased humidity)

Recording the data

Measuring the butterflies’ sizes

A group photo – 11D class and Mrs. Ioana Stoica