Skip to content

SANParks.org Forums

View unanswered posts | View active topics






Post new topic Reply to topic  Page 1 of 2
 [ 21 posts ]  Go to page 1, 2  Next
Author Message
 Post subject: Geckos
Unread postPosted: Wed Apr 19, 2006 1:25 pm 
Offline
Honorary Virtual Ranger
Honorary Virtual Ranger
User avatar

Joined: Fri Jan 14, 2005 5:42 pm
Posts: 17943
Location: Red sand, why do I keep thinking of red sand?
Classification
Class Reptilia (reptiles)
Order Squamata (lizards and snakes)
Suborder Lacertilia (lizards)
Family Gekkonidae (geckos)

About 400 species exist.

The family Gekkonidae is divided into five different subfamilies, containing numerous different genera of gecko species.

Habitat
Geckos live in a variety of warm habitats, including rainforests, deserts, grasslands, and marshes.

Anatomy
Geckos have short, wide, fleshy toes with large, backward-curved claws. Most geckos have sticky toe pads, sesert geckos have fringed feet that let them run across sand very easily. Flying geckos (genus Ptychozoon) have wide flaps of skin extending from the abdomen and have webbed toes, legs, and tail that help them glide gracefully through the air.
Geckos range in size from 1.5 to 35 cm long, the largest gecko is the Tokay gecko (Gecko gecko).
Geckos are the only lizards that have a voice. Some species of geckos make a squeaking or clicking noise that sounds like "gecko," hence their name.

Most geckos are tan to dark grey, subtly patterned, and somewhat rubbery looking. Some species can change color to blend in with their surroundings or with temperature differences. However others can be brightly colored. Geckos regularly shed their skin.

Many species have specialized toe pads that enable them to climb smooth vertical surfaces and even cross indoor ceilings with ease. (More on that below.) These antics are well-known to people who live in warm regions of the world where several species of geckos make their home inside human habitations. These species (for example the House gecko) become part of the indoor menagerie and are seldom really discouraged because they feed on insect pests. Many geckos are kept as pets, the most popular is the Leopard Gecko (Eublepharis macularius). They are arboreal and nocturnal so you will not see them much during the daytime hours.

With eyesight comparable to a cat's, geckos can see better than any other lizard. Geckos cannot blink since instead of an eyelid they have one transparent scale, which covers the eye. If their eyes are dirty, the gecko licks them clean with its large fleshy tongue.

Diet
Gecko are carnivores. They eat mostly insects (like crickets, springtails, and cockroaches) and mealworms, but they also eat young birds, eggs, and tiny mammals, hunting for their prey at night.

Defense
Snakes are the gecko's main predators. As a defense against predators Gecko's will drop their tails. A muscular spasm separates the tail at a specialized fracture point found in some of the tail vertebrae while a related adaptation clamps off blood vessels to prevent hemorrhaging. A new tail will begin to grow in a few weeks, but instead of a column of distinct bony vertebrae, it will have a less flexible rod of calcified cartilage. If the remaining original part still has a fracture point, the lizard can autotomize its tail again. A newly lost tail twitches violently until the nerve impulses run down, and is very likely to hold the predator's attention while the lizard escapes. Arboreal species, which use their tails extensively as a fifth limb when climbing, are less likely to drop the tail than ground dwelling species.
Geckos use the tail for fat storage, so the gecko needs to have plenty food until the tail has regrown.

Propagation
Geckos are quite prolific breeders. Mating usually occurs at night and two eggs will generally be laid after around 60-70 days. Incubation time ranges from 39 to 62 days. The females can lay up to five clutches a year. The temperature at which the eggs incubate decides the sex of the young ones. The rule of thumb for Leopard Gecko is that eggs incubated at 26°C result in female hatchlings. Male hatchlings will be produced at 32°C, and at 29°C a percentage of both sexes will be realized. The eggs are soft at first, but harden quickly. There is no parental care. Geckos will sometimes eat their own eggs.

Some species are parthenogenic, the females capable of reproducing without copulating with a male. This improves the geckos' ability to spread to new islands.

Lifespan
This depends on the species of course, but they can reach ages of around 20 years, and in captivity even 36 years has been reported.

How do they stick?
The little lizards have a network of tiny hairs and pads on their feet which produce electrical attractions that literally glue the animals down. With millions of the hairs on each foot, the combined attraction of the weak electrical forces, known as Van der Waal forces, that allow the gecko to stick to virtually any surface - even polished glass. Geckos have developed an amazing way of walking that rolls these hairs onto the surface, and then peels them off again, just like tape.
There are millions of micron-scale adhesive foot-hairs on each toe. Each foot-hair splits into hundreds of tips only 200 nanometers in diameter, permitting intimate contact with rough and smooth surfaces alike. Geckos' adhesive microstructure requires minimal attachment force, leaves no residue, is directional, detaches without measurable forces, is self-cleaning, and works underwater, in a vacuum, and on nearly every surface material and profile.
A single gecko foot hair (which is named a seta) was taken and direct measurement of its adhesive function was taken.

It was discovered that the seta is 10 times more adhesive than predicted from prior measurement on whole animals. The adhesive is so strong that a single seta can lift 20 mg (The weight of an ant.). A million setae could lift the weight of a child (20kg). A million setae could easily fit onto the area of a Dime. The combined attraction of a billion spatulae is a thousand times more than a gecko needs to hang from the ceiling. Maximum potential force of 2,000,000 setae on 4 feet of a gecko = 2,000,000 x 200 micronewton = 400 newton = 40788 grams force, or 40 kilo's! This is 600 times greater sticking power than friction alone can account for.

Van der Waals forces
Named after a 19th-century Dutch physicist, van der Waal forces are weak electrodynamic forces that act over relatively short distances and are responsible for the cohesion of molecular crystals and liquids. The forces stem partly from dipole to dipole interactions, but even nonpolar molecules and atoms exert a certain attraction to one another. Ultimately, this short-range molecular attraction allows the gecko to stick to nearly every surface.

_________________
Arriving currently: The photos from our trip! Overhere! :yaya:

Feel free to use any of these additional letters to correct the spelling of words found in the above post: a-e-t-n-d-i-o-s-m-l-u-y-h-c


Top
 Profile  
 
 Post subject: Gecko
Unread postPosted: Mon May 07, 2007 5:40 pm 
Offline
Junior Virtual Ranger
Junior Virtual Ranger
User avatar

Joined: Sun Sep 04, 2005 3:04 pm
Posts: 537
Location: Nottinghamshire UK
Any information about this lizard? Seen in Lower Sabie camp on the restaurant wall in February. A new one on me - never seen anything like it in 20 years!

Richard

Image


Top
 Profile  
 
 Post subject:
Unread postPosted: Tue May 08, 2007 2:11 pm 
Offline
Honorary Virtual Ranger
Honorary Virtual Ranger
User avatar

Joined: Fri Jan 14, 2005 5:42 pm
Posts: 17943
Location: Red sand, why do I keep thinking of red sand?
Transvaal thick-toed gecko (Pachadactylus affinis)
Got one of them in a kill, also in LS:

Image

_________________
Arriving currently: The photos from our trip! Overhere! :yaya:

Feel free to use any of these additional letters to correct the spelling of words found in the above post: a-e-t-n-d-i-o-s-m-l-u-y-h-c


Top
 Profile  
 
 Post subject:
Unread postPosted: Sun Feb 17, 2008 2:53 pm 
Offline

Joined: Mon Jan 31, 2005 12:00 am
Posts: 36
Location: Nelspruit
This is actually Turner's Thick-toed Gecko, Pachydactylus turneri.


Top
 Profile  
 
 Post subject:
Unread postPosted: Thu Feb 28, 2008 5:08 pm 
Offline
Junior Virtual Ranger
Junior Virtual Ranger
User avatar

Joined: Tue Sep 26, 2006 12:20 pm
Posts: 469
We have losts of them at Marloth - bordering Kruger. They smaak sitting against our windows. :lol:


Top
 Profile  
 
 Post subject:
Unread postPosted: Tue Mar 18, 2008 2:08 pm 
Offline
Honorary Virtual Ranger
Honorary Virtual Ranger
User avatar

Joined: Fri Jan 14, 2005 5:42 pm
Posts: 17943
Location: Red sand, why do I keep thinking of red sand?
An interesting article about the use of the tails of geckos can be found at the BBC website.

_________________
Arriving currently: The photos from our trip! Overhere! :yaya:

Feel free to use any of these additional letters to correct the spelling of words found in the above post: a-e-t-n-d-i-o-s-m-l-u-y-h-c


Top
 Profile  
 
 Post subject:
Unread postPosted: Tue Mar 18, 2008 7:33 pm 
Offline
Senior Virtual Ranger
Senior Virtual Ranger
User avatar

Joined: Sat Jul 15, 2006 8:40 pm
Posts: 2780
Location: At work
Amazing stuff! Thanks, DQ. :D

_________________
Only two things are infinite, the universe and human stupidity, and I'm not sure about the former. - Albert Einstein (1879-1955)


Top
 Profile  
 
 Post subject: Gecko I.D
Unread postPosted: Wed May 12, 2010 9:25 pm 
Offline
User avatar

Joined: Wed Feb 11, 2009 1:34 pm
Posts: 334
Location: Johannesburg
Hi,

Could anybody help me identify this gecko I found at Tamboti?

Image

Image

Thanks,

Samantha


Top
 Profile  
 
 Post subject: Re: Gecko I.D
Unread postPosted: Thu May 13, 2010 6:59 pm 
Offline
Junior Virtual Ranger
Junior Virtual Ranger
User avatar

Joined: Sun Aug 16, 2009 6:54 pm
Posts: 2105
Location: Sabie
:hmz: looks like a Tropical House Gecko , but I'm not a Gecko fundi :doh:

_________________
IF A TREE FALLS IN THE FOREST AND NO ONE HEARS IT FALL...DO YOU THINK THEY SHOULD HAVE THEIR EARS TESTED ?


Top
 Profile  
 
 Post subject: Re: Gecko I.D
Unread postPosted: Thu May 13, 2010 7:32 pm 
Offline
Virtual Ranger
Virtual Ranger

Joined: Wed Mar 03, 2010 10:29 am
Posts: 1664
Location: Worcester , Cape
We also saw some a couple days ago in Tambotie . Looks no different from the ones we get in Cape Town , and also surrounding areas .
So I would certainly have some doubts about calling them " Tropical " ??

_________________
Tread softly , and let your departure not be spoiled by the damage of your arrival

Next :
3 - 6 Sept 2013 - Punda.
7 - 10 Sept 2013 -Shingwedzi .
11 - 13 Sept 2013 - Balule .
14 - 17 Sept 2013 - Satara .


Top
 Profile  
 
 Post subject: Re: Gecko I.D
Unread postPosted: Thu May 13, 2010 7:47 pm 
Offline
Junior Virtual Ranger
Junior Virtual Ranger
User avatar

Joined: Sun Aug 16, 2009 6:54 pm
Posts: 2105
Location: Sabie
we get cape buffalo up here in the lowveld :hmz:

_________________
IF A TREE FALLS IN THE FOREST AND NO ONE HEARS IT FALL...DO YOU THINK THEY SHOULD HAVE THEIR EARS TESTED ?


Top
 Profile  
 
 Post subject: Re: Gecko I.D
Unread postPosted: Thu May 13, 2010 9:36 pm 
Offline
Junior Virtual Ranger
Junior Virtual Ranger
User avatar

Joined: Wed Jun 08, 2005 4:24 pm
Posts: 1170
Location: UK
I saw loads of these at Satara and Olifants. They seem to be quite common.


Top
 Profile  
 
 Post subject: Re: Gecko I.D
Unread postPosted: Fri May 14, 2010 1:58 pm 
Offline
Virtual Ranger
Virtual Ranger

Joined: Wed Mar 03, 2010 10:29 am
Posts: 1664
Location: Worcester , Cape
forestgump wrote:
we get cape buffalo up here in the lowveld :hmz:



:clap: :clap: :clap:

_________________
Tread softly , and let your departure not be spoiled by the damage of your arrival

Next :
3 - 6 Sept 2013 - Punda.
7 - 10 Sept 2013 -Shingwedzi .
11 - 13 Sept 2013 - Balule .
14 - 17 Sept 2013 - Satara .


Top
 Profile  
 
 Post subject: Re: Gecko I.D
Unread postPosted: Fri May 28, 2010 5:10 pm 
Offline
Junior Virtual Ranger
Junior Virtual Ranger
User avatar

Joined: Tue Sep 16, 2008 11:11 pm
Posts: 2626
Location: Sunninghill(JHB), Vaalwater & Beauty(Waterberg), Grahamstown(E.C)
Looks like a tropical house gecko to me too

_________________
:dance: STIFFNECKS MEMBER :dance:

FGASA LEVEL 1


Top
 Profile  
 
 Post subject: Re: Gecko I.D
Unread postPosted: Sat Oct 23, 2010 7:19 pm 
Offline
Virtual Ranger
Virtual Ranger
User avatar

Joined: Sat Mar 29, 2008 7:05 pm
Posts: 2674
Location: Looking for Bats...
Mareous Tropical House Gecko :D

_________________
Avid birder, wildlife enthusiast and photographer with a special interest in Bats

2014 Birding Big Year- A 365 Day quest for 800 Species of Southern African Birds
Stiffnecks Member


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 21 posts ]  Go to page 1, 2  Next



Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group

Webcams Highlights

Addo Nossob Orpen Satara
Addo Nossob Orpen Satara
Submitted by Jurie van Vuuren at 12:26:03 Submitted by teddy_rsa at 14:19:08 Submitted by grannyb at 23:42:22 Submitted by grannyb at 22:32:14