Thread by @je_light

First up in Kat's Away division, Orinoco Crocodile (#1 seed) vs Goliath Tarantula (#9 seed) #2018MMM

This battle was written by the fabulous @c_n_anderson, & it's a doozy. Buckle up folks #2018MMM

The critically endangered Orinoco crocodile defeated the praying mantis in R1 and faces another arthropod tonight. arkive.org/orinoco-crocod… #2018MMM

Traditionally, most crocodilians have been thought of as a polygynous species (males mating multiply, females with a single reproductive partner) en.wikipedia.org/wiki/Polygyny_… #2018MMM

But with DNA-based approaches, researchers have discovered that the mating system may be best characterized polygynandry (multiple mating by both males and females) en.wikipedia.org/wiki/Polygynan… & journals.plos.org/plosone/articl… #2018MMM

Up against South America's largest crocodile tonight is South America's (and the world's ) largest spider #2018MMM

The goliath tarantula defeated a pit viper to get here, and faces a (much larger) reptile arkive.org/goliath-bird-e… #2018MMM

Tonight's battle begins on the banks of the Cojedes River in Venezuela. The Orinoco Croc lies in wait arkive.org/orinoco-crocod… #2018MMM

The Goliath Tarantula is probing the banks for a site to dig a burrow - but it does not realize that it is probing nesting habitat for the Orinoco Crocodile #2018MMM

The croc rises from the shallows, snapping its giant mouth and startling the spider arkive.org/orinoco-crocod… #2018MMM

Goliath Tarantula raises into defensive posture to show its fangs, & then flicks off some abdominal bristles at the croc. Urticating "hairs" is a defense mechanism used by all new world tarantulas en.wikipedia.org/wiki/Urticatin… #2018MMM

Tarantula "hair" isn't made of keratin (like ours) instead it is chitin-based. Fun fact, while it was thought that hair was only found in mammals, there is evidence for hair keratin genes in the genomes of birds and reptiles news.nationalgeographic.com/news/2008/11/0… #2018MMM

There is probably only one spot on a crocodile that a tarantula bristle would do ANY good in a MMM battle. The eyes! And that is exactly were our urticated hair is headed! #2018MMM

The Orinoco Croc closes it's third eyelid and the bristle bounces off harmlessly. That's right, @c_n_anderson said third eyelid. Crocodiles (like birds and fish) have a nicitating membrane. Here's a youtube video of a crocodile blinking one #2018MMM

Human's have a vestigial nictitating membrane at the corner of their eyes called the Plica semilunaris en.wikipedia.org/wiki/Plica_sem… #2018MMM

After the blink the crocodile lunges at the Goliath tarantula and CHOMPS! #2018MMM

ORINCO CROCODILE CHOMPS GOLIATH TARANTULA! #2018MMM