Abstract
In aggressive mimicry,a predator accesses prey by mimicking the appearance and/or behavior of a harmless or beneficial model in order to avoid being correctly identified by its prey.The crab spider genus Phrynarachne is often cited as a textbook example of masquerading as bird droppings(BDs)in order to avoid predation.However,Phrynarachne spiders may also aggressively mimic BDs in order to deceive potential prey.To date,there is no experimental evidence to support aggressive mimicry in masquerading crab spiders;therefore,we performed a field survey,a manipulative field experiment,and visual modeling to test this hypothesis using Phrynarachne ceylonica.We com-pared prey-attraction rates among BDs,spiders,and control empty leaves in the field.We found that although all prey combined and agromyzid dipterans,in particular,were attracted to BDs at a higher rate than to spiders,other dipterans and hymenopterans were attracted to BDs at a similar rate as to spiders.Both spiders and BDs attracted insects at a significantly higher rate than did con-trol leaves.As predicted,prey was attracted to experimentally blackened or whitened spiders sig-nificantly less frequently than to unmanipulated spiders.Finally,visual modeling suggested that spiders and BDs can be detected by dipterans and hymenopterans against background leaves,but they are indistinguishable from each other.Taken together,our results suggest that insects lured by spiders may misidentify them as BDs,and bird-dropping masquerading may serve as aggres-sive mimicry in addition to predator avoidance in P.ceylonica.
基金项目
National Natural Science Foundation of China(NSFC32070430)
National Natural Science Foundation of China(31872229)
Singapore Ministry of Education AcRF Tier 1 grant(R-154-000-B18-114)
NETL
NSTL
维普
万方数据