Ticks can “smell” you (or your pet) and will be attracted to areas that you or your pet frequent. In these locations they will wait for you (or your pet) to pass and with extended forelegs attempt to attach themselves. Ticks then crawl upward (always proceeding) against gravity and to find a warm, moist, soft spot of skin where they can insert their sucking mouth parts to draw your blood (and perhaps infect you with dangerous disease germs too. .
The ticks we all too often encounter in our gardens, jogging, or walks in the woods are most likely the common “deer tick” Ixodes scapularis. These tiny, (1/8 inch) arthropods, distantly related to spiders (and also with eight legs) are a serious and dangerous pest for those of us who love the outdoors.
When mature these tiny arthropods are only the size of a sesame seed, though the young ( nauplii stage) are less than the size of the head of a pin (about one millimeter across). Both the mature tick and the young, seek nutrition in the form of blood from hosts. Once fully engorged with blood, they fall off to complete their life cycle by either laying eggs, or by seeking a secondary host animal (after which they complete their life cycle by laying eggs).
Ticks are barely visible, flat, hard bodied, eight-legged arthropods which have a small head that is fused to their thorax, and a large flat abdomen. Under the dissecting microscope, the tiny head and mouthparts of the tick are revealed as intriguing (and frightening) as well as exceedingly efficient. The mouth organ consists of a central siphon tube which leads to the gut, bounded on either side by a sharp-pointed harpoon-like appendage armed with sharp, rear-facing barbs. These paired “harpoon” appendages are able to move forward and back, sliding along the side of the siphon tube. The paired “harpoons” on either side of the siphon tube move forward and back alternately, acting to insert the siphon tube and the head deep into the skin of the host. The mouth organs function to bury the head deep below the epidermis to reach the capillary -rich dermis. This insures the tick a source of blood and also establishes a firm “headhold” to lock the tick’s essential mouthparts in place and insure that it remains in the host’s skin (even after the host animal begins to sense its presence (itching and inflammation) and initiates attempts to scratch it away.
To remove a fully inserted tick completely, with such mouth organ armament is near impossible, once it has firmly and deeply attached itself in the skin. A fine pointed forceps is often recommended to grasp the head and attempt to withdraw it first without detaching the head from the tick. . (Do not grasp the bloated body since this may simply force fluids from the tick into your skin). The result of attempts at tick removal often end with a good part of the head, barbed parts and siphon remaining embedded in the host. There they can remain often causing( long term itching and inflammation.
These eight legged, blood sucking arthropods are no recent addition to our fauna, they have been with us since the Age of the Dinosaurs. Ticks which look just like our modern species have been found embedded in amber (fossilized tree sap) that dates to the late part of the Cretaceous Period, or about 99 million years ago. One family of ticks found in South Africa and possibly the most ancient of the line is known to parasitize native African lizards upon whose blood they feed. So it is conceivable that the ancestors of our modern ticks living in the Cretaceous may have first evolved to the blood of ancient reptiles and perhaps dinosaurs too! .
So over those millions of years of evolution and adaptation, ticks have evolved very efficient ways to find and attach to their reptilian or mammalian hosts. Observational evidence suggests that ticks can SCENT the presence of their hosts and actually move to areas where these scents are stronger where they wait in anticipation of a passing host animal. A personal experience in a heavily forested area on Long Island during a field survey illustrates this effective means of scenting and finding their hosts.
It was many years back, while working on an archeological survey on a Long Island property had a dense deer populations and was heavily infested with deer ticks. My crew of university students were dressed in standard field attire : long pants, with pant leg’s tucked into their socks, long sleeved collared shirts tucked into the pants and with shirt collars turned down. This mode of dress helped prevent ticks, which have the (nearly) unique characteristic of only crawling “upward” (against gravity).
Finding a tick on a branch of leaf—you can make it change course by turning the branch or leaf upright and then as the tick moves upward, turn it down and the tick will reverse course and head in the opposite (upward) direction always going opposite to the “pull” of gravity. Ticks are programmed to be “anti-geotropic” (to move opposite to the force of gravity). When students followed the “archeology field-dress code they most often escaped becoming hosts for ticks . Often the ticks they did attract were found lodged under their down-turned shirt collars, reaching that point, but unable to go downward, they remained trapped under the shirt collar.
Late in the afternoon on this particular field day, as we completed subsurface testing of a brushy section of the wooded property one of our test pits .revealed evidence suggesting the presence of a possible subsurface prehistoric native-American site. After additional shovel tests in the area, the team was directed to clear the thick brush. We subsequently oriented and laid out a one-meter square excavation unit to evaluate the subsurface for further detailed study. The corners of this test square were established by driving four, one-by-one inch wood stakes into the ground at the four corners. This work was completed late in the day, and further excavation was put off for the next day.
On the following morning, our team arrived at the site and began to prepare for more detailed excavation. As one of the students attempted to wrap twine used as a “level line” on each stake, she noted that the top of the corner stake was occupied by six or eight adult ticks. Each one was observed standing on its rear legs on the sharp corner edges of the one-inch square stake. Each tick’s assumed a “praying-mantis” pose or grasping attitude, with its fore legs extended, ready to grasp and climb on to any unsuspecting host coming into range. Each one of the stakes was occupied by similar numbers of ticks ready to hitch a ride on any host fur or clothing brushing past.
Apparently, the ticks were able to “smell” mammal body fluids (perhaps persiration) left on the stakes by the sweaty hands of the excavation team members. Zoologists note that ticks have an olfactory organ on their fore legs (I.e. Haller’s Organ). It appeared that our disturbance and presence within the brushy area, as well as the scent of mammal body odors and body fluids may have attracted all the local ticks from the surroundings to the area of our proposed test excavation, where they climbed on to top of the stakes to wait for their prey to return!!
Team members, always ready with Deep Woods “Off”, sprayed down the stakes and the offending parasite critters and wiped them away. Then continued to successfully excavate the test unit. (It was positive at depth for prehistoric evidences, perhaps dating to nearly a millennia ago.)
Thus it is clear that the movement of animals or humans through brushy areas where ticks may be located can attract ticks which use scent or “smell” to locate potential mammal hosts, then climb into position so as to increase the chance of encountering a host
Recurrent passage of a pet such as a cat or dog through a brushy pathway, its waste, and regular use of an area may attract ticks which can scent the presence of their hosts and migrate to these areas. So beware.
A handy means of extracting a recently attached tick to your skin can be fashioned from a thin plastic water bottle or thin aluminum soft drink can The bottom of the bottle or can is cut off with a pocket knife. The base is saved. A small “v” shaped cut is made into the top edge of the base (about 1/2 cm wide). The base of the “v” notch is extended downward about 0.5cm with the knife blade to make a slit LI. The base is then used to extract the tick by scraping the “v” along the skin surface so as the slit in the plastic passes under the tick body. The buried head of the tick can now be removed by gently tugging on the base. The tick’s body should be captured within the base.
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