bombardier beetle biology, habitat mechanism

1. “under a piece of bark I found two
carabi & caught one in each hand. Lo
& behold I saw a sacred Panagaeus
crux major; I could not bear to give up
either of my Carabi, & to lose
Panagaeus was out of the question, so
that in despair I gently seized one of
the carabi between my teeth, when to
my unspeakable disgust & pain the
little inconsiderate beast squirted his
acid down my throat & I lost both
Carabi & Panagaeus!”
(Charles Darwin, 1846 )

2. Believe it or not,
there are some
bugsyou don’t
wantto putinyour
mouth
Cychrus caraboides

4. CONTENTS

5. Introduction
(Eisner, 2005)
 When provoked by predators , Bombardier beetles
mix together a concoction of chemicals within their
abdomen to give out an explosive spray.
 This explosion has an audible 'pop‘ sound and
visible puff of chemical which is expelled at a high
temperature.

7. Taxonomy
Kingdom : Animalia
Phylum : Arthropoda
Subphylum : Hexapoda
Class: Insecta
Order : Coleoptera
Suborder : Adephaga
Family: Carabidae
Subfamily : Brachininae,
Paussinae
• Two subfamilies
1. Brachininae: Brachinini
and Crepidogastrini
2. Paussinae: Paussini,
Protopaussini, Ozaenini,
Mystropomini and
Metriini
( Erwin,1970)

8. Brachininae
Tribe Brachinini
Brachy: refers to truncated elytra
 540 species
 Ectoparasites in their larval stage, feeding on
carabid and water beetle pupae.
 Achieve the highest spray temperatures
(100˚C) and velocities (10 m/s)
 Eg: Brachinini bonelli
(Bousquet, 2012)

9. Tribe Crepidogastrini
 112 species
 Distributed primarily in Africa with a
few species found in India.
 Secretion emerges as a mist.
 Reaction chambers are asymmetrical, with the
more laterally positioned lobe enlarged and
elongated relative to the other.
 Eg: Crepidogaster bioculata
(Bousquet, 2012)

10. Paussinae
Tribe Paussini
 565 species
 Myrmecophiles –
Ant nest beetles.
 Acoustic mechanism- imitate the
sounds of an ant queen thus
enter the ant nest without
alarming them.
 Coanda effect
(Andrea, 1842)

11. Tribe Protopaussini
 8 spp, Native to Asia
 Myrmecophilous
Tribe Mystropomini
 Two species, native to Australia.
 Not suspected to associate with
ants.
 The temperature has been
measured to be 40˚C.
(Bousquet, 2012)

12. Tribe Ozaenini
160 species
 Defensive spray temperatures and
velocities of 65˚C and 2.4 m/s
Tribe Metriini
Two species native to China.
Temperature is 55˚C, secretes a
chemical mist.
Only paussoids that lack elytral
flanges.
(Bousquet, 2012)

13.  Various species of bombardier beetles can be
located in every continent except in Antarctica
 This beetle occurs in central and southern
Europe and North Africa, reaching as far north
as central Sweden.
 Brachinus fumans- lives only in North America
 In India species belonging to family paussidae
and tribe crepidogastrini are mostly found.
(Poetker, 2013)
Distribution

14. Biology
 Complete metamorphosis
 Lay egg on pile of mud, or
dead and decaying plants
 3 larval instars, parasitic
 Adults 6.5- 9.5 mm in
length
(Erwin, 2009)

15. Habitat and Behaviour
 Most prefer to live in temperate forests
or grasslands, but the Brachinus fumans lives
in deserts, savannas, chaparral, and forests.
 It resides mostly in woodlands and undisturbed
riverbanks and floodplains.
 Nocturnal in its habits, hiding by day under stones
and tree bark, while hunting at night.
 Carnivorous (predators and scavengers ), including
the larva, feeding on other insects.
(CSIRO, 2014)

16. Defence Mechanism
 Pair of organs which produce the secretion,
termed pygidial glands
 Located inside at either side of the abdomen tip.
 Each gland comprises a cuticle-lined cavity as
well as muscle and secretory tissues
 Reservoir chamber - aqueous solution of 25%
hydrogen peroxide and 10% 1,4-hydroquinones
 Reaction chamber - catalases and peroxidases
(Schildknecht, 1961)

17. 100˚C

18. (Michael, 2015)
RSC: RESERVOIR CHAMBER
RXC: REACTION CHAMBER
EC: EXIT CHAMBER
RP: REFLECTOR PLATE
Brachinus elongatulus
(Schildknecht, 1961)

19. Hydrogen Peroxide
Hydroquinones
One-way
Valve
Peroxidase
and
Catalases
Defence Mechanism Overview
1
2
3
3. Peroxidase and catalase
Lining the wall of reaction
chamber rapidly catalyse
the oxidation of
Hydrogen peroxide and
hydroquinone resulting in
a boiling explosion of
water, quinone, heat and
oxygen. The reaction is
jet propelled through the
abdomen of beetle
2. These chemicals are
forced into reaction
chamber by means of a
one way valve controlled
by muscle contraction.
1. Hydrogen peroxide and
hydroquinone secreted
into collection reservoir

20. Chemistry
(Beheshti, 2006)
 C6H6O2 (aq) + H2O2 (aq) → C6H4O2 (aq) + 2H2O (l).......... (1)
 C6H6O2 (aq) → C6H4O2 (aq) + H2 (g) ................................. (2)
 H2O2 (aq) → H2O (l) + ½ O2 (g)…………………………………….…(3)
 H2 (g) + ½ O2 (g) → H2O (l)..................................................(4)
 ∆ H2 = +177.2 kJ/mol
 ∆ H3 = −94.5 kJ/mol
 ∆ H4 = −285.5 kJ/mol
 ∆ H1 = −202.8 kJ/mol

21. (James, 2012)

22. ICV – INTER CHAMBER VALVE
VM – VALVE MUSCLE
EM- EXPANSION MEMBRANE
VO- VALVE OPENING
Brachinus elongatulus (Michael, 2015)

23. (Michael, 2015)

24. (Michael, 2015)(Michael, 2015)

25. Spray durations
 Spray durations
5.0 ± 0.5ms to
344 ± 4ms
 80% of the
discharges lasting
40ms
(Michael, 2015)

26.  Spray pulsation rates 341- 976 Hz
 Number of pulse 2-22
(Michael, 2015)
Averagepulsationrate

27.  Exit channel opening or closing- 2.5- 86.5ms
 Reactant droplet mass 5.5± 0.6 µg
 The percentage of females tested that recorded
spraying was much less than that of males
(4.35% of 69 females vs. 15.7% of 70 males)
 Female sprays tended to be longer in duration
than male discharges, as reflected in their
median durations (68.8ms for 6 female sprays
vs. 20.8ms for 24 male sprays)
(Michael, 2015)

28. How chemical is stored?
 Quinone chemicals are
a precursor to sclerotin.
 Some beetles additionally store
excess foul-smelling quinones,
including hydroquinone, in small
sacs below their skin as a
natural deterrent against
predators.
 Hydrogen peroxide, a common
by-product of the metabolism of
cells (Brunet, 1955)

29. (Schildknecht, 1970) (Michael, 2015)

30. Evolutionary peculiarity
 One of the better-known examples of the organ
development problem is the bombardier beetle’s
‘spray gun’.
 To achieve the spray, bombardier beetles possess
specialized glands which lie on either side of
abdomen.
 Critics have argued that the chemicals are not
actually explosive, but they do produce much heat
and pressure in a chamber that could explode if not
controlled and properly regulated.
(Weber, 1981)

31. (Mark Isaak, 2007)

32. EFFECT ON VICTIMS
 Effect of Thermal and Chemical
Components of Bombardier
Beetle Chemical Defence on
Glossopharyngeal Response in
Two Species of Toads
 Repeated stimulation destroys
general tongue sensitivity.
 The end result was the frogs’
aversion to the beetles.
(Dean, 1980)

33. • Solid line represents responses of marine toads;
• Dashed line represents those of American toads.
(Dean 1980)

34. Avoiding predation…
 Orb -weaving spider of the
genus Argiope
 Mud -dwelling larva of the
horse fly Tabanus
 Blue jays (Cyanocitta
cristata)
 Antlion larvae
(Eisner, 2005)
 Grasshopper mouse

35. Why beetle doesn’t paralyze
itself?
 Highly sclerotized
pygidial gland
 Helicoidal organization
of lamina
 Gland is composed of
cuticle and that the
reaction chamber is stiffer
than the sac-like reservoir
chamber
 Little valves ensures that
explosives don’t flow back
(Michael, 2015)

36. NEW INSIGHTS

37. Biomimetic
(Beheshti. 2007)
Biomimetics is the
application and abstraction
of biological methods,
systems and good designs
found in nature to the study
and design of efficient and
sustainable engineering
systems and modern
technology.

38. Challenge of emissions
reduction
 The beetle’s capability has
ability to tune the size of
the droplets down to as
little as 2 µm.
 This greatly increases the
burning efficiency of the
fuel, since the surface area
increases greatly and
consequently, less fuel is
burned, and thus pollution
is reduced.
(McIntosh, 2008)

39. A scaled-up version
of the combustion
chamber
((Beheshti, 2007))

40. Gas turbine aircraft engine
(Thompson, 2003)

41. Fire extinguishers
(Mclntosh, 2007)

42. Anti -vandalism mechanism
for ATMs
( Stark, 2014)
 Hydrogen peroxide and
magnesium dioxide in two
different structure.
 This could be used anywhere
on things that shouldn't be
touched.
 Cost effective , Does not
need electricity to operate.
 Emit dye with DNA
nanoparticle, mark them for
tracking.

43. Conclusion