The forgotten predators: ant- and termite-eating mammals Acknowledgements
Patchy Ubiquitous
Prof. William Bond (ideas); Prof. Mark Robertson; Prof. Kate Parr and Dr. Paul Eggleton top-down bottom-up “Population density (of ants) is constrained by kinds of food and nest sites, as well as by predation.”
“Predators, especially visually searching vertebrate predators, play a key role ... rivalling the maximization of net energetic yield as a natural selection factor.”
Holldobler and Wilson. 1990. The Ants. 113 3 1
leaf-cutter ant nest size
control exclosure
Hirsch et al., 2014 1
VERY LARGE
LARGE
MEDIUM
SMALL
Hirsch et al., 2014 Terborgh et al., 2001 2 Terborgh et al., 2001 Trophic Cascade 2 Chinese Pangolin
Nine-banded Armadillo
Common Echidna
Giant Anteater Aardvark Orycteropus afer Redford (1987)
216 extant species
cross-continental comparison
Our database (2019)
291 extant + 40 extinct species = 331 extinct mammals extant
extinct # of species of #
mass (kg)
ANT DEFENCE AGAINST MAMMALS
1. Bites & Stings 2. Nest Design 3. Flight Response 2. NEST DESIGN Predator Digging Depth
0.18m Echidna Numbat
Opiang, 2009
2.25m
Aardvark Pangolin Aardwolf
Taylor & Skinner, 2003 Milewski et al., 1994 Echidna Numbat
Tschinkel, 2004; 2011
Nest design where predators only scratch the surface? Aardvark Pangolin Aardwolf
Tschinkel, 2004; 2011 Nest design where predators are large and dig deep? FORMICINE DOLICHODERINE Anoplolepis custodiens Iridomyrmex purpureus
40cm
400cm
Longitudinal section through A.custodiens nest on the island of Zanzibar
Ettershank, 1968 TERMITE DEFENCE AGAINST MAMMALS
1. Mound Hardness 2. Soldier 3. Digging Morphology distance to the queen 1. MOUND HARDNESS Echidna
Giant Anteater 50 x harder than soil at the base
Cornitermes cumulans
Negret and Redford CONCLUSIONS
different
1. predict greater differences in ant and termite biology btw.
Africa and Australia than btw. Africa and South America
2. largely threatened mammals
3. megafauna of the ant and termite world
Time to integrate mammal predation into ant and termite community ecology!
cross-continental termite predictions
similar major + minor soldier castes single soldier caste
+ developed mandibles under-developed mandibles soldier: worker ratio soldier: worker ratio
+++ hard mounds soft mounds no design constraint relating to the greater digging distance to the queen position of the queen ant genus with highest abundance in diet of predator
FORMICINE DOLICHODERINE Anoplolepis Iridomyrmex
Lindsey and Skinner, 2001 Abensperg-Traun et al., 1991