Myrmarachne colombiana. Credit: George Poinar Jr. A fossilized ant-mimicking spider reveals the evolutionary techniques spiders use to avoid predators, stressing the adaptive advantages of mimicry in the spider kingdom.Arachnophobia can make people run away at the sight of a brown recluse, black widow, or perhaps a daddy long legs, but animal predators of spiders understand no such fear.Thats why, paleobiologist George Poinar Jr. discusses, some spider types have developed the defense of deception. They masquerade as a much less desirable prey– ants– and Poinars recent paper in Historical Biology provides an early record of an ant-mimicking spider in fossilized resin.Ants: The Perfect Disguise for Spiders” Ants are especially good creatures for spiders to pretend to be– numerous animals discover ants distasteful or hazardous to consume,” said Poinar, who has a courtesy consultation in the Oregon State University College of Science. “Ants are aggressive in their own defense– they have a strong bite along with a stinging venom, and they can hire lots of nestmates as allies. Spiders, meanwhile, have no chemical defenses and are loners, that makes them vulnerable to being hunted by bigger spiders, birds and wasps– predators that would rather prevent ants. If a spider can be like an ant, its more most likely to be unbothered.” Fossil Discovery and Evolutionary AdaptationsSpiders that camouflage themselves as ants live in many locations around the world but previously most had actually had the ability to avoid detection from fossil scientists as well as predators. The specimen that Poinar explains, which he called Myrmarachne colombiana, was entombed in a type of fossilized resin referred to as copal.Copal is a less mature form of fossilized resin than amber, which is consistently dated to be 25 million or more years old. Still, copal can be as much as 3 million years old.The age of the resin in this case, nevertheless, could not be determined, said Poinar, a worldwide specialist in using plant and animal life forms preserved in amber to find out about the biology and ecology of the distant past.The resin block he was dealing with, which came from Medellin, Colombia, was too little to age-test without risk of harming the spider inside. Poinar keeps in mind there is no record of any currently living ant-mimicking spider making its home in Colombia.” It is a challenge for spiders to accomplish this magical change to ants,” he said. “Ants have six legs and two long antennae, while spiders have eight legs and no antennae.” To navigate those physiological distinctions, Poinar stated, spiders typically position their two front legs in a manner that approximates the look of antennae. Number of legs and absence/presence of antennae are not the only characteristics distinguishing an ants look from a spiders.” The abdomen and cephalothorax of spiders are carefully connected, while in ants the equivalent of these body parts are separated by a narrow segment called the petiole,” Poinar said. “And there are many other lesser structures that need to be customized in spiders for them to closely look like ants. How is this achieved? Many researchers state it begins with spider anomaly, adaptation, and then natural selection.” However, I believe there is some spider thinking and intelligence involved too considering that the spiders often design their body changes after particular ants in the very same environment,” he said. “In the early days, we were informed that all practices of pests were the outcome of instincts, but that is no longer the case.” Spider Mimicry: A Widespread PhenomenonSeveral groups of spiders have established the capability to behave and look like various types of ants, he included. There are likewise spiders that attempt to blend in as other insects, such as flies, beetles, and wasps.Most of the copycat spiders belong to a few households of searching spiders, consisting of Salticidae or jumping spiders. The specimen in the Colombian copal seems a leaping spider.Spiders that practice mimicry also come from the Corinnidae (sun spider), Thomisidae (flower spider) and Zodariidae (spotted or ant spider) families.Reference: “Myrmarachne colombiana sp. n. (Araneae: Salticidae), a new types of ant-mimic spider in copal from Colombia, South America” by George Poinar, 7 March 2024, Historical Biology.DOI: 10.1080/ 08912963.2024.2320190.
Credit: George Poinar Jr. A fossilized ant-mimicking spider reveals the evolutionary tactics spiders utilize to prevent predators, highlighting the adaptive benefits of mimicry in the spider kingdom.Arachnophobia can make people leave at the sight of a brown recluse, black widow, or even a daddy long legs, but animal predators of spiders understand no such fear.Thats why, paleobiologist George Poinar Jr. describes, some spider species have developed the defense of deceptiveness. They masquerade as a much less preferable victim– ants– and Poinars current paper in Historical Biology presents an early record of an ant-mimicking spider in fossilized resin.Ants: The Perfect Disguise for Spiders” Ants are particularly good animals for spiders to pretend to be– numerous animals discover ants horrible or harmful to consume,” said Poinar, who has a courtesy appointment in the Oregon State University College of Science. There are also spiders that attempt to blend in as other pests, such as flies, beetles, and wasps.Most of the copycat spiders belong to a couple of families of hunting spiders, including Salticidae or jumping spiders. The specimen in the Colombian copal appears to be a jumping spider.Spiders that practice mimicry likewise come from the Corinnidae (sun spider), Thomisidae (flower spider) and Zodariidae (spotted or ant spider) families.Reference: “Myrmarachne colombiana sp.
