Coordination of movement via complementary interactions of leaders and followers in termite mating pairs.

Leadership of animal group movements depends on social feedback, hence
leader’s signals and follower’s responses should be attuned to each other.
However, leader and follower roles are difficult to disentangle in species
with high levels of coordination. To overcome this challenge, we
investigated a simple case of movement coordination: termite pairs in
which a female leads a male as they search for a nest site. To tease apart
leader and follower roles, we created conspecific and heterospecific pairs
of Coptotermes gestroi and C. formosanus, which share a pairing pheromone
so that males follow females of either species. Conspecific pairs were
stable for both species, even though C. gestroi females produce less
pheromone than C. formosanus. Heterospecific pairs with C. gestroi males
were also stable, but not those with C. formosanus males. We attributed
this difference to the C. gestroi male’s unique capacity to follow females
that release small amounts of pheromone; C. formosanus males cannot follow
or reject C. gestroi females as unsuitable. This conclusion was supported
by an information-theoretic analysis that detected information flow from
female to male in only stable tandems. Despite their following ability, C.
gestroi males lost to C. formosanus males in competitions to follow C.
formosanus females. Thus, partner selection has shaped the
species-specific association of mating pairs. Our results demonstrate that
a similar level of coordination can emerge from distinct sets of
complementary sender-receiver interactions.

动物群体移动的领导权依赖于社会反馈，因此领导者的信号与跟随者的响应应当彼此适配。然而，在高度协同的物种中，领导者与跟随者的角色很难厘清。为克服这一难题，我们研究了一种简单的移动协同案例：雌雄配对行进的白蚁，其中雌性引领雄性搜寻筑巢位点。为厘清领导者与跟随者的角色，我们构建了格斯特乳白蚁（Coptotermes gestroi）与台湾乳白蚁（C. formosanus）的同种配对与异种配对组合；二者共享配对信息素，因此雄性可跟随任一物种的雌性。两种物种的同种配对均保持稳定，尽管格斯特乳白蚁雌性分泌的信息素少于台湾乳白蚁雌性。带有格斯特乳白蚁雄性的异种配对同样保持稳定，但带有台湾乳白蚁雄性的异种配对则不然。我们将这一差异归因于格斯特乳白蚁雄性独特的跟随能力——其可跟随释放少量信息素的雌性；而台湾乳白蚁雄性无法跟随格斯特乳白蚁雌性，或会将其判定为不适配对象。这一结论得到了信息论分析的支持：该分析仅在稳定的成对行进组合中检测到了雌性向雄性的信息流动。尽管具备跟随能力，格斯特乳白蚁雄性在争夺跟随台湾乳白蚁雌性的竞争中败给了台湾乳白蚁雄性。因此，配偶选择塑造了交配配对的物种特异性关联。我们的研究结果表明，相似水平的协同行为可源自不同的互补发送者-接收者交互模式。