Monday, January 25, 2016

Behavioral analysis of Madagascar Hissing Cockroaches





Methods

                In our study of these insects, our procedure consisted of timed periods of study. Specimens were placed in a clear plastic container with pieces of graph paper as the substrate at the bottom, allowing hiding, but providing a clear contrast to the dark-colored specimens. At intervals throughout the study period, modifications were made, such as the addition of food or a hide to the tank, the turning off of a overhead light, and the addition of a second specimen. After the study period ended, a seperate specimen was examined in various behaviors, such as reaction to being flipped over or having air blown onto them. This period was not timed, but instead ended when all possible procedures had been performed upon specimens.

Results

                During examination period, the main observations involved three basic behaviors, namely moving across the tank, staying in one place, or twitching the antennae. Other behaviors were documented as slight modifications on these three, documenting how antennae were being twitched or the speed that the cockroach was moving at.

                When cockroaches were handled, brushed, or otherwise touched or disturbed, unless the interaction was a slight brush on the middle of the back, the roaches reacted strongly, usually either hissing or dodging away or towards the disturbance. From these observations in captivity, I predict that in the wild, these insects have many predators and use these methods of avoidance to keep themselves alive.

                When new hide objects were added or the substrate was moved, the roaches would often either avoid the new or moved object or hide underneath it. This shows that these insects may prefer to be underneath leaves or rotting logs in their native habitat, slowly devouring the decomposing plant.

                In righting and avoidance behaviors, the responses differed noticeably in the reaction. Avoidance behavior seemed to take longer to react and was much less sudden. However, when the roaches were flipped over, all quickly would right themselves via bending their bodies up and to the side, forcing their weight towards the ground in the proper orientation.

                The cerci were observed to produce the distinctive hissing sound when the cockroach was disturbed. I am not entirely sure why the cerci produce this sound, but my particular theory is that, by producing the sound from the cerci, a cockroach may be able to convince a predator that its tail is a false head, letting the creature lunge for the tail, but not killing the roach. This behavior is common in reptiles and winged insects, but until now, I had not observed it in a roach or termite. This shows that optimal behaviors for survival are almost universal, regardless of the animal that is carrying them out.

                The timed study period is documented in the table on the next page, as is graphical analysis of the amounts of time spent doing the three most common behaviors.








                The graph above displays the number of minutes the roaches spent doing each of the three most common actions. The precise values are 7 minutes for sitting or otherwise not moving, 5 minutes and 40 seconds for crawling or otherwise moving around the tank using the legs, and 19 minutes (the entire period) for twitching antennae. This value may seem surprising for twitching antennae, but at least one of the roaches studied, even while sitting or crawling, was twitching their antennae throughout the entire period.


Time
Behavior
Notes
0:10
going underneath paper bedding

0:20
sitting

0:30
twitching antennae

0:40
crawling

0:50
twitching antennae

1:00
quickly crawling

1:10
exploring other side of tank

1:20
sitting

1:30
moving mouthparts

1:40
crawling

1:50
moving to other side of tank

2:00
no change

2:10
twitching antennae

2:20
crawling

3:00
twitching antennae

3:30
cleaning antennae?
moving antennae down and touching with mouthparts. behavior unknown.
4:40
sitting

5:00
no change
cardboard added, tube in middle of tank
5:10
twitching antennae slightly

5:20
antennae stopped twitching

6:00
asleep?
has not moved for some time in any way
6:30
twitching antennae slightly

6:40
sitting

6:50
sitting

7:00
twitching antennae

7:10
antennae stopped twitching

7:40
twitching antennae

8:00
no change
food added, piece of banana
8:30
sitting

9:00
twitching antennae slightly

9:15
moving mouthparts

10:00
no change
added second roach, known as Small. Previous roach Big.
10:10
Small and Big interacting, touching mouthparts
smelling or feeling?
10:30
Small hiding underneath Big

10:40
Big antennae twitching

11:00
Small still hiding under Big

12:00
no change

13:00
no change

14:00
no change

15:00
no change until Small handled to be removed, then hissed

15:00
Small removed, light added

15:00
climbing away from light

15:30
walking around side of tank, away from light

16:00
moving more slowly

16:30
moved into middle of tank, stopped hugging wall

16:50
crawling

17:00
no light, crawling

17:45
hugging wall

18:00
climbing wall

18:30
sitting, antennae twitching

19:00
cleaning antennae


Saturday, January 23, 2016

Breaking News:Warm-blooded lizards?!

Yes, warm-blooded lizards have been discovered. They aren't dinosaurs, and this is not a drill. More precisely, a recent discovery is that the tegu, a popular species of monitor, can provide itself with endothermic body heat. The only strange thing about this, other than the fact that until recently, everyone knew lizards were cold-blooded, is that the tegu only uses its heating system at certain times of the year. Despite comprehensive studies being performed about the issue, nobody currently knows how the tegu generates the heat. The current hypothesis is that the reptile secretes a hormone that causes some of its body parts to go into overdrive, which produces heat. However, this hypothesis has not yet been proved. Expect it to be proved, disproved, or replaced by other theories in future studies. Another theory surrounding not only this endothermic lizard but the rise of warm-blooded animals in general is that endothermy evolved gradually, as breeding modified metabolic systems. As a result, many animals may have gone through phases where they had partial endothermy, as the tegu has been discovered to undergo.

Irwin, Aisling. "First warm-blooded lizards switch on mystery heat source at will" https://www.newscientist.com/article/2074982-first-warm-blooded-lizards-switch-on-mystery-heat-source-at-will/

Science AdvancesDOI: 10.1126/sciadv.1500951

Thursday, January 21, 2016

Entomology Field Trip:Parody of "Tick Tock" by Ke$ha

Goin' to the park, hey, cool! I found this bug
(Hmm, what is it?)
I'm pullin' out the smartphone, got my field guide on.
(Okay)
I think I've got some idea 'bout what this is
It's probably a darkling beetle, this app says

I'm talking larvae that look like worms, worms
To move around it squirms, squirms
Eats lots of plants and herbs, herbs
Often found infesting grain, grain
It's got a really small brain
Has to go and hide in the rain.

Hey, look what I found
Just a-crawling on the ground
Being driven insane
'Til we find its Latin name
Now it's under a rock
But the study don't stop, no oh oh oh oh
oh oh oh oh

Hey, look what I found
Just a-crawling on the ground
Being driven insane
'Til we find its Latin name
Now it's under a rock
But the study don't stop, no oh oh oh oh
oh oh oh oh

The flies, they just flit around the garbage can
Just looking for some food to feed their mouthparts and
They're seeing through their compound eyes like lots of mirrors
But when it comes to finding them, it couldn't be clearer!

I'm talking puttin' out a piece of fruit, fruit
They go to it on their route, route
They're buzzing, 'cause they just aren't mute, mute

Now, now, we study 'em till we find out
About their favorite kind of sprout, sprout
Their favorite kind of sprout, sprout
Favorite kind of sprout


Hey, look what I found
Just a-crawling on the ground
Being driven insane
'Til we find its Latin name
Now it's under a rock
But the study don't stop, no oh oh oh oh
oh oh oh oh

Hey, look what I found
Just a-crawling on the ground
Being driven insane
'Til we find its Latin name
Now it's under a rock
But the study don't stop, no oh oh oh oh
oh oh oh oh



Hey, look, what is this thing?
Well, does it sing?
I think it might
be invasive

Straight from Japan
it eats our plants
It came in
shipments right to us

Hey, look, what is this thing?
Well, does it sing?
I think it might
be invasive

Straight from Japan
it eats our plants.
It eats our plants!

Gotta tell all my folks we got a new foreign threat


Hey, look what I found
Just a-crawling on the ground
Being driven insane
'Til we find its Latin name
Now it's under a rock
But the study don't stop, no oh oh oh oh
oh oh oh oh

Hey, look what I found
Just a-crawling on the ground
Being driven insane
'Til we find its Latin name
Now it's under a rock
But the study don't stop, no oh oh oh oh
oh oh oh oh