You need more than just one experiment to claim it as true. A lot more research has to be done and it has to be tested on more species.What is there not to believe? Its a scientific experiment.
That is the second link I posted.The 2006 paper with A. seemani was refuted shortly after, this paper uses several species. Here is the summary to save some surfing:
Rind, C., et al. Tarantulas cling to smooth vertical surfaces by secreting silk from their feet. Journal of Experimental Biology 214, 1874-1879.
Like all spiders, tarantulas (family Theraphosidae) synthesize silk in specialized glands and extrude it from spinnerets on their abdomen. In one species of large tarantula, Aphonopelma seemanni, it has been suggested that silk can also be secreted from the tarsi but this claim was later refuted. We provide evidence of silk secretion directly from spigots (nozzles) on the tarsi of three distantly related tarantula species: the Chilean rose, Grammostola rosea; the Indian ornamental, Poecilotheria regalis; and the Mexican flame knee, Brachypelma auratum, suggesting tarsal silk secretion is widespread among tarantulas. We demonstrate that multiple strands of silk are produced as a footprint when the spider begins to slip down a smooth vertical surface. The nozzle-like setae on the tarsi responsible for silk deposition have shanks reinforced by cuticular thickenings, which serve to prevent the shanks' internal collapse while still maintaining their flexibility. This is important as the spigots occur on the ventral surface of the tarsus, projecting beyond the finely divided setae of the dry attachment pads. We also reveal the structure and disposition of the silk-secreting spigots on the abdominal spinnerets of the three tarantula species and find they are very similar to those from the earliest known proto-spider spinneret from the Devonian period, giving another indication that silk secretion in tarantulas is close to the ancestral condition.
TEM of tarsal setae would be a bit tough to pull off, and also finding anyone who can actually do histology at that level, ouch. Although cryo-TEM would greatly simplify the process, identifying the glads would still be difficult. I don't know of anyone working on this in theraphosids. Most of the current buzz is from material engineers who have kicked the tires and more people are actually looking.I'll support the tarsi silk production idea when someone finds the silk glands responsible for it.
Oh, okay. Sorry about that!TEM of tarsal setae would be a bit tough to pull off, and also finding anyone who can actually do histology at that level, ouch. Although cryo-TEM would greatly simplify the process, identifying the glads would still be difficult. I don't know of anyone working on this in theraphosids. Most of the current buzz is from material engineers who have kicked the tires and more people are actually looking.
I've been pondering repeating this experiment with some of my spiders, I mean it's pretty simple to take a tarantula and run it onto a slide and see if there is any webbing left behind, if they slip. I'll have a better idea once I lay hands on the original paper with mats and methods.
And yes, I know the link was the same, I posted the summary to save some clicking, as many folks cruise the boards via phones.
I take this back now that I've read the article at the National Geographic site. I can't wait to read the research finding in the Journal of Experimental Biology when it is published.I'll support the tarsi silk production idea when someone finds the silk glands responsible for it.
Yes, I'm quite proficient with SEM. In addition to several rounds of sputter coating (or increasing coating time), it's useful to tilt the stub platform in the coater, to ensure better coverage. Also, you might need to add some silver paint to the base of the leg to ensure better grounding. The shorter the specimen the better, if it's directed away from the stub.Kirk,
You know SEM at all?
I took some quick shots from C. cyanopubescens and the setae look very similar to the P. regalis in Fig. 4 A. I'll try to upload them soon, sadly I'm off work the next couple of days and forgot them on the server.
The main problem I was having was charging, but the sample has gone into a 48C oven and I'll sputter coat again and peak next week. I could not see any setae with pores.