Iberianature Forum

weird things in the ground

  • 16 Replies
  • 12677 Views

0 Members and 1 Guest are viewing this topic.

Offline Jill

  • *
  • Sr. Member
  • ****
  • Posts: 494
    • Jill Dickin Schinas
« on: March 13, 2007, 13:50 PM »
Hullo,
My daughter spends most of the day grovelling in the dirt, looking at creepy crawlies, and she is forever finding things that I can't identify. A couple of months ago she sent the following letter to various people, including the Natural History Museum in London, and the children's section of the RSPB:

Hello,
This is Roxanne. I am 9 years old. I live in Spain, in a sunny, dry, sandy place. It is quite hot, especially in summer. Last December, on a patch of waste, we (my mother and I) discovered lots of little mounds, each about 3 inches tall, like a clay pot, or a hole with a wall around it. They stood in little clusters of 3 or 4, made of loose earthy soil. I dug one up, but the tunnel underneath just went round in a circle ending again by the doorway! Next time I found a ant in it. Do you know what they are?
Roxanne

The museum didn't answer. The RSPB suggested that they might be the holes made my ant-lions. If that's the case, they have jolly big ant-lions around here! The only ant-lion pits that I have studied were nothing like this; they were just funnel-shaped pits in the ground. Somebody else suggested that Roxanne's pot-makers might be wasps. Does anybody else have any ideas?
(I've tried attaching a photo but I can't seem to make it small enough.)

All the best, Jill

Offline nick

  • *
  • Administrator
  • Full Shroomy
  • *****
  • Posts: 1948
    • Iberianature
« Reply #1 on: March 13, 2007, 14:42 PM »
Do sound like ant lions, but no expert. Have a look at photos here http://en.wikipedia.org/wiki/Antlion

 I'm sure this is one for Clive and Sue. Send me the photo and I'll resize it for you.

Cheers
Nick
« Last Edit: March 13, 2007, 14:47 PM by nick »
Nick
http://iberianature.com/barcelona/history-of-barcelona/spanish-civil-war-tour-in-barcelona/
Spanish Civil War Tours in Barcelona
http://www.iberianature.com/
A guide to the environment, climate, wildlife, & nature of Spain
The Amazon/Forum Bookshop - lend us a hand
http://www.iberianatureforum.com/shop/index.htm
And also now The Natural History of Britain
http://iberianature.com/brita

Offline Clive

  • *
  • Administrator
  • Full Shroomy
  • *****
  • Posts: 2990
  • Sierra de Grazalema
    • Wildside Walking Holidays - Spain
« Reply #2 on: March 13, 2007, 20:33 PM »
Hola,

Just to get you going here is a very good scientific piece on what I suspect is a relative of Roxanne's little beastie.

http://www.vernalpools.org/Thorp/

The fact that it lives in a place other than Iberia is not so important.

The amazing thing is to see the interaction between these creatures and plants and to realise how even a humble solitary bee is an important part of our everyday world.

Not so long ago I saw an article on the BBC news web site that had pictures of burrowing solitary bee nests that had been fossilised but i just can't find it now.

Also Roxanne, You are describing two different types of nest, I think. One is a pile of soily sandy granules with a hole in the middle going straight down and the other is a formed jar like structure. Maybe you have a colony of burrowing bees and an adjacent colony of some creature that parasitises them.

Can you remember which type was there the most?

I think we need that picture when you get time to send it to Nick.

Clive
Explore the nature of Iberia at www.wildsideholidays.com

The beautiful town of Ronda, the City of Dreams?

The spectacular Caminito del Rey, El Chorro and Guadalhorce reservoirs El Camino del Rey

Offline nick

  • *
  • Administrator
  • Full Shroomy
  • *****
  • Posts: 1948
    • Iberianature
« Reply #3 on: March 13, 2007, 21:03 PM »
Here you go. Here's Roxanne's photo:

Nick
http://iberianature.com/barcelona/history-of-barcelona/spanish-civil-war-tour-in-barcelona/
Spanish Civil War Tours in Barcelona
http://www.iberianature.com/
A guide to the environment, climate, wildlife, & nature of Spain
The Amazon/Forum Bookshop - lend us a hand
http://www.iberianatureforum.com/shop/index.htm
And also now The Natural History of Britain
http://iberianature.com/brita

Offline Clive

  • *
  • Administrator
  • Full Shroomy
  • *****
  • Posts: 2990
  • Sierra de Grazalema
    • Wildside Walking Holidays - Spain
« Reply #4 on: March 13, 2007, 21:12 PM »
Hola,

I've changed my mind it's not a bee....I think umm....

Still That bee link I gave earlier was pretty cool huh?

Clive
Explore the nature of Iberia at www.wildsideholidays.com

The beautiful town of Ronda, the City of Dreams?

The spectacular Caminito del Rey, El Chorro and Guadalhorce reservoirs El Camino del Rey

Offline Clive

  • *
  • Administrator
  • Full Shroomy
  • *****
  • Posts: 2990
  • Sierra de Grazalema
    • Wildside Walking Holidays - Spain
« Reply #5 on: March 13, 2007, 21:21 PM »
Hola,

Ants, after a rain storm, clean out their nests and some of the larger species create mounds like this.

Where in Spain is this picture taken and more importantly, did it rain a few days before the picture was taken...

I just love the Idea of 9 years old Roxanne peering into the living world....

Clive
Explore the nature of Iberia at www.wildsideholidays.com

The beautiful town of Ronda, the City of Dreams?

The spectacular Caminito del Rey, El Chorro and Guadalhorce reservoirs El Camino del Rey

Offline Jill

  • *
  • Sr. Member
  • ****
  • Posts: 494
    • Jill Dickin Schinas
« Reply #6 on: March 13, 2007, 22:35 PM »
 
  Dear Clive,and every one else
 This is  me,Roxanne,(but I am not very good at typing!) Mummy and I saw those things at La Manga,near Murcia on a patch of land with lots of dry,sandy,salty,soil,waiting to have blocks of flats built on them,(not much left now!).I dont think it had been raining.I found a ant in there, but mummy thinks it wandereid in....   It was in December,not much rain then.I have seen them since but not so big and perfect.                                                                                                                                                                             Mummy and I sent a letter before with the photo.It isnt there for some reson...Yet.

              Love Roxanne

  ps. Ive got another Thingy I suppose I had better do in another letter.Clever this thing!

Offline nick

  • *
  • Administrator
  • Full Shroomy
  • *****
  • Posts: 1948
    • Iberianature
« Reply #7 on: March 14, 2007, 20:22 PM »
Hi Roxanne,

I'm not very good at typing either and it's part of my job so don't worry about that. Did you send the letter to me? Can't see it in the email

Thanks
Nick
Nick
http://iberianature.com/barcelona/history-of-barcelona/spanish-civil-war-tour-in-barcelona/
Spanish Civil War Tours in Barcelona
http://www.iberianature.com/
A guide to the environment, climate, wildlife, & nature of Spain
The Amazon/Forum Bookshop - lend us a hand
http://www.iberianatureforum.com/shop/index.htm
And also now The Natural History of Britain
http://iberianature.com/brita

Offline Jill

  • *
  • Sr. Member
  • ****
  • Posts: 494
    • Jill Dickin Schinas
« Reply #8 on: March 14, 2007, 21:01 PM »
We sent it, seemingly, in the same instant that you posted the photo, Nick - so perhaps the machine didn't like getting two identical photos at the same moment. The letter didn't say much; just a few words (of no great relevance) about that excellent ground nesting bee website which Clive directed us too.

Jill

Offline steveT

  • *
  • Sr. Member
  • ****
  • Posts: 314
« Reply #9 on: May 13, 2007, 11:41 AM »
Dear all,

These are antlion pits, the lava of this damslefly looking creature, build these pits. They are built in dry earth. Their size is related to the 29.5 day cycle of the moon - as the moon wanes the holes get smaller.....nobody knows why. Inside the hole you see fine particles all the big ones have been removed, by the grub. This means that insects that get too near the edge fall in and fall to the bottom as the sides are smooth ( a sort of event horizon on the micro scale!! ). The pincered grub at the bottom ( just below surface ) grabs them. ......and until yesterday I knew nothing about antlions .....I just happened to see similar pictutres in this months BBC Wildlife Magazine.ticle ..there's a short article about them.

steveT

Offline nick

  • *
  • Administrator
  • Full Shroomy
  • *****
  • Posts: 1948
    • Iberianature
« Reply #10 on: May 13, 2007, 12:57 PM »
29.5 day cycle. How bizzare.
Nick
http://iberianature.com/barcelona/history-of-barcelona/spanish-civil-war-tour-in-barcelona/
Spanish Civil War Tours in Barcelona
http://www.iberianature.com/
A guide to the environment, climate, wildlife, & nature of Spain
The Amazon/Forum Bookshop - lend us a hand
http://www.iberianatureforum.com/shop/index.htm
And also now The Natural History of Britain
http://iberianature.com/brita

Offline Clive

  • *
  • Administrator
  • Full Shroomy
  • *****
  • Posts: 2990
  • Sierra de Grazalema
    • Wildside Walking Holidays - Spain
« Reply #11 on: May 13, 2007, 13:19 PM »
Hola,

My goodness, can you imagine if these guys were the size of dogs? It reminds of that bit in starwars when jabba the hut was going to throw Hans solo and Luke into that funny sand pit in the desert.

http://www.antlionpit.com/what.html has a good explanation with images.

Clive
Explore the nature of Iberia at www.wildsideholidays.com

The beautiful town of Ronda, the City of Dreams?

The spectacular Caminito del Rey, El Chorro and Guadalhorce reservoirs El Camino del Rey

Offline Technopat

  • *
  • Full Shroomy
  • ******
  • Posts: 3020
« Reply #12 on: May 13, 2007, 13:39 PM »
Greetings All,
Weird AND amazing!
That 29.5 day cycle ...
I think, Roxanne, you have found your true calling in life!
Regs.
Technopat
Technopat's disclaimer: If this posting seems over the top and/or gets your goat (Sp. anyone?), please accept my apologies and don't take it personally - it's just my instinctive tendency to put my foot in it whenever/wherever possible. See also:
http://www.iberianatureforum.com/index.php/topic,266

Offline steveT

  • *
  • Sr. Member
  • ****
  • Posts: 314
« Reply #13 on: May 13, 2007, 19:23 PM »
The  lunar cycle is 29.5, not 28 days ..... somehow this forms part of an internal clock. Apparently, in the lab they still follow this cycle.

SteveT

Offline Jill

  • *
  • Sr. Member
  • ****
  • Posts: 494
    • Jill Dickin Schinas
« Reply #14 on: May 15, 2007, 17:47 PM »
Ahoy, over there!

It feels weird to be speaking to you from this distant, (very) damp isle.... (Is it allowed, or do I have to wait till I come home?)

Sorry, folks, but I still don't believe that the creations which sparked off this particular column are antlion pits. I have not come across any antlion pits in Spain, but I know the South African species of the creature quite well. The kids once dug one up and put him (or her) in a tub with some loose earth, and sure enough, he dug a pit and captured the ant which was dropped into his domain. We didn't keep this "pet" long enough to notice its observance of the lunar cycle. It would be jolly interesting to do so.

The antlion pits that we saw in SA were funnel shaped - and so are the ones on the website that Clive has discovered. (I seem to recall that there's some good stuff on Wikipedia, also.) Perhaps the photo doesn't make it very clear, but the things which we found at La Manga are really pots, rather than pits; they are elevated above the ground. If we find any more I'll get Rox to grovel on the ground and take one looking sideways at it ! I've a feeling that they are probably built like this specifically to prevent things such as ants from falling in...

Roxanne has dug up a couple of these weird things, hoping to find the occupant. On each occasion there seemed to be a very narrow tunnel underneath (whereas the antlion just lies there, just under the surface, and has no need for a tunnel). The tunnel appeared to be a loop, starting and ending at the "pot". In the first of the two pots investigated there was one ant occupying this "burrow", and in the second, three baby woodlice. We do not believe that their Mummy was the architect.

One thing that the pots do have in common with the antlion pits is that they sometimes occur in clusters. However, antlion pits (in SA, at any rate) tend to be under trees, whereas these occur on open ground.

Does anybody on the forum have antlions living near them?
 
I still favour Clive's wasp or bee theory, but I have to say that I find it hard to understand how any small creature could build this large and beautiful pot-like structure. Perhaps I have placed them under the wrong heading... Next time we find one of these things - if and when we ever do - we will sit and watch it for a good long while before excavating. Perhaps a snake will crawl out !

Jill

Offline steveT

  • *
  • Sr. Member
  • ****
  • Posts: 314
« Reply #15 on: May 17, 2007, 00:47 AM »
Dear Jill,

I've just gone back to the article on antlions in the BBC wildlife magazine an don the net, and on second examination ..... the antlions pits, are pits with no raised bit ......so your right they are probaly not antlions.....

SteveT

Offline Jill

  • *
  • Sr. Member
  • ****
  • Posts: 494
    • Jill Dickin Schinas
« Reply #16 on: September 25, 2007, 18:58 PM »
Mystery solved !

And Clive was right - as usual. 

Ever since I posted the picture of the weird, pot-shaped creations in the sandy soil, we've been keeping an eye out, looking for more. Specifically, we went to look after each rain storm, but no luck. Today, for the first time, there are half a dozen new pots. They are in more or less the same place as the old ones.

Well, we stood there for a while, trying to decide whether to dig (we'd tried this before and found nothing) or whether to leave well alone and post a 24 hour watch, seven days a week, to see who might enter or exit. (Even Roxanne baulked at that idea.) While we were disputing the matter, who should appear from out of the hole but a largish ant - and he was carrying in his forearms (?) a grain of sand as large as his head.
"Told you so," said Rox (which was true. Based on the fact that she had once found one small ant under one of the pots, she had decided that they were ant-made).
I was still not convinced; I was hoping for something more exotic or exciting, such as a scary spider or a huge wasp. However, while we watched the ant(s) continued to emerge and descend repeatedly, each time lugging a single grain of sand and adding it to the top of the wall.

What a project! I suppose it is just possible that the ants were just taking over somebody else's pre-excavated home, and tidying up, but it didn't seem that way. On the contrary, what we saw seemed to be proof positive that ant colonies are slave states - for who but slaves could be persuaded to go to all that trouble for the good of the community and the queen !

Jill