Argentine Ants | The Global Super Colony — Transcript

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1. 0:00Hi, my name's Jordan Dean.
2. 0:03In this video we're going to be looking into the lives of the exceedingly infamous Argentine
3. 0:09Ants.
4. 0:16Argentine Ants, known scientifically as Linepithema humile, are native
5. 0:21to parts of South America.
6. 0:24But through human activity, they’ve now established themselves all over the world
7. 0:28and are considered to be one of the worst invasive ant species out there.
8. 0:34The ants are highly problematic to introduced regions, as they can disrupt the fragile balance
9. 0:39of the native ecosystems, and subsequently, diminish their levels of biodiversity.
10. 0:46They do so by displacing native animal populations.
11. 0:50Taking them as prey, and or, out competing them for resources.
12. 0:57Many native ant species often fall victim to these invaders.
13. 1:01As the Argentine Ants prey upon insects commonly eaten by these natives, and are often much
14. 1:07faster in discovering them too, leaving little to no food around for them to consume and
15. 1:13develop their colonies.
16. 1:16They’re also extremely hostile towards any rival ants.
17. 1:21Here you can see some Argentine Ants aggressively fighting over this source of food, which was
18. 1:27initially discovered by this native species of Big-headed Ants…The native ants defend
19. 1:34their find with everything they’ve got…But in the end, their efforts are wasted, as the
20. 1:44Argentine ants overwhelm them with their superior numbers…So a source of food which was once
21. 1:50feeding a native colony, is now promoting the strength of these troublesome invaders…
22. 1:59Argentine Ants are also known to invade the nests of smaller ant colonies.
23. 2:03Here, they’re raiding the nest of another native species.
24. 2:08so as to feed their ever growing colony.
25. 2:13But why should it matter if one ant species is replaced by another?
26. 2:19Well, the weakening and eventual loss of these native ant colonies, greatly impacts the ecology
27. 2:25of the area.
28. 2:27The natives are perfectly adapted to living alongside and subsequently supporting the
29. 2:32local plants, by cycling and enriching their soil...
30. 2:38dispersing and protecting their seeds...
31. 2:43and sometimes, even aiding in their pollination too.
32. 2:49Once Argentine Ants replace these native ants, all of a sudden, the seeds, once tended to
33. 2:55by the former ants, are left untouched, as the Argentine Ants have little to no interest
34. 3:01in the seeds or favor the seeds of different plants, like nonnatives and weeds.
35. 3:08They also don’t dig very deep within the ground like most ants do.
36. 3:12Instead, they prefer to nest fairly close to the grounds surface.
37. 3:17This too negatively effects the surrounding plant life, as they lose the assistance of
38. 3:21having well cycled and enriched soil, which the native ants readily provided.
39. 3:33Argentine ants can even attack such animals directly, overwhelming them with their immense
40. 3:37Targeting birds and reptiles by invading their nests and consuming the vulnerable young as
41. 3:42they hatch.
42. 3:55So what makes these Argentine Ants so successful at dominating their surrounding environment?
43. 4:01They aren’t overly large, only measuring 3-4mm in length, and don’t possess venomous
44. 4:07stings like Fire Ants do, or have the ability to spray acid like Yellow Crazy Ants.
45. 4:14But instead, these ants possess some highly advantageous abilities, and what they lack
46. 4:19for in size and lethality, they greatly make up for in numbers.
47. 4:25Normally, when you have two separate ant colonies come together, even those of the same species,
48. 4:33they clash, sometimes, having to fight out to the death in order to protect or expand
49. 4:38their territory.
50. 4:43The reasoning for this is because the foreign ants have a different chemical profile to
51. 4:47those of their own colony.
52. 4:50Native colonies of Argentine Ants are no different.
53. 4:54They form relatively small colonies which are genetically diverse, each having its own
54. 4:59unique scent.
55. 5:01But the introduced Argentine Ants are unlike those from their homeland.
56. 5:07Because there has been little to no diversification, they are genetically similar, and so, possess
57. 5:13chemical profiles which are almost identical from colony to colony.
58. 5:18So ants from separate colonies, tens, hundreds, even thousands of kilometers apart, rarely
59. 5:23compete with one other.
60. 5:26Instead, they cooperate.
61. 5:30To demonstrate just how cooperative these Argentine Ants can be, we’re going to be
62. 5:35looking inside the nest of captive colony.
63. 5:39Currently, the colony is only quite small, with under 100 total individuals.
64. 5:45But in a few moments, this colony is about to triple in size.
65. 5:52Inside this vile, I’ve got a bunch of ants and brood which I’ve collected from a mature,
66. 5:57foreign colony of Argentine Ants.
67. 6:00So let’s see what happens when I expose them to this young colony here…
68. 6:07As soon as the lid’s taken off, they’re away, scanning the surrounding area and surveying
69. 6:12their options...
70. 6:19Within a short while, they discover the foreign nest, and shortly after, start picking up
71. 6:25all their brood and moving them straight in with theirs…
72. 6:43In virtually all other species of ants, this combination of two different colonies would
73. 6:49result in complete chaos, and each group would be fighting it out to the death.
74. 6:55This cooperative merging together of colonies, means these Argentine Ants are able to form
75. 7:00colonies on a massive scale, spanning hundreds, even thousands of kilometers.
76. 7:13The ants are also polygynous too, meaning they will accept more than one egg laying
77. 7:18queen within their individual colonies.
78. 7:22Notice these slightly larger ants here?
79. 7:25These are actually all queen ants, and each colony often has at least several of these
80. 7:29queens present.
81. 7:31Resulting in large batches of eggs being laid and rapid growth of the ants’ population.
82. 7:38They’re also incredibly adaptable when it comes to their nesting environment.
83. 7:43Typically, they nest beneath rocks and leaf litter...
84. 7:50and in and underneath logs...
85. 7:56and sometimes, even up within the trees.
86. 8:04And they’re highly mobile too.
87. 8:07Often up and moving their entire colonies if the conditions aren’t favorable.
88. 8:14After this captive colony’s recent spike in population, they’re starting to look
89. 8:19a little cramped within their little test tube, and naturally, would be scouting around
90. 8:23for a preferable nesting site.
91. 8:28So what I’ve done here is attached up an alternative space for them to explore, a small
92. 8:34prototype formicarium we’ve been working on here at Ants Australia.
93. 8:41The new area is kept both humid and dark.
94. 8:44Ideal living conditions for the colony.
95. 8:48Almost as soon as it’s attached up, the ants begin inspecting the new space…
96. 8:59Once they deem it suitable, the message is spread rapidly throughout the colony.
97. 9:05And within moments, the ants start moving on in, brood, queens and all...
98. 9:40Before long, their old nest is completely abandoned in favour of the new…
99. 9:54Argentine Ants also use their speedy repositioning skills for another important purpose, reproduction.
100. 10:02Typically, when ants undergo their nuptial flights, the winged reproductive ants, known
101. 10:08as alates, fly off in search of foreign alates to mate with.
102. 10:15The newly mated queens will then shed their wings, and search for a safe place to lay
103. 10:22their eggs and form new colonies.
104. 10:26Argentine Ants are a little strange, in that the female alates have wings, but rarely ever
105. 10:32use them.
106. 10:33Instead, most of the mating actually occurs within the ants’ nests.
107. 10:38They’re able to spread in a process known as “budding”.
108. 10:42This is where ants branch off on foot, in groups consisting of a single queen or more,
109. 10:49along with a number of worker ants.
110. 10:51Each group then relocates and establishes themselves within new nesting sites.
111. 10:58So the ants are effectively dividing and multiplying their numbers, gradually expanding the territory
112. 11:05of their species.
113. 11:08A far less perilous method when compared to the more common, nuptial flights.
114. 11:20From appearance alone, Argentine Ants look rather ordinary and insignificant.
115. 11:28But withall their exceptional traits, like being able to merge their colonies...
116. 11:35Their tolerance of multiple queens...
117. 11:40Their ability to occupy a large variety of habitats...
118. 11:45And their exceptional colony manoeuvrability...
119. 11:50you can see just why they are such a dominant species and are so
120. 11:54effective at monopolizing their surrounding environments.