Spiders, silk and goats

Kruger National Park | April 2019

The mere mention of the word “spider”, and many people will have a shiver running down their spine, and most likely, the majority of guests coming on safari would not add seeing spiders on their wish list of top ten things to encounter and get close to when in the African wilderness. With that being said however, many people are actually pleasantly surprised and intrigued when they do see one of the most elegant of arachnids: the orb web spiders.

The golden orb web spiders are most likely the most well-known of these web dwellers. The females are large colourful spiders, the size of a child’s hand, whilst the males are considerably smaller and drab in colour. Upon closer inspection, sometimes small silvery drops resembling mercury can also be spotted in the web. These are kleptoparasitic dewdrop spiders that will live on the edge of the web, where they will carefully scavenge any prey items that the bigger orb web spider might miss.

The golden orb web spider has a large characteristic web that is constructed in open areas, with a diameter varying between a few centimetres to several metres. Their webs also have a characteristic golden colour, giving rise to the group’s common name.

Spider silk is considered as one of the seven wonders of the animal kingdom. It is extremely strong, and it can stretch. Spider silk, on a per-weight basis, with the ratio of strength to density exceeds that of steel. It is therefore not uncommon to find a variety of insects, and even small lizards and birds entangled in the webs.

With spider webbing being such a strong material, many scientists have attempted to farm it on a large scale. It is however very difficult to produce spider silk commercially, because spiders kept in spider farms tend to kill and eat each other because they are territorial.

So, you might ask, what do spiders, silk and goats have in common?

To solve this problem, professors and researchers of molecular biology at the University of Wyoming decided to put spiders’ dragline silk gene into goats in such a way that the goats would produce silk protein in their milk. It is believed that there could be numerous uses for this product, specifically in the medical field. It could be used to produce artificial ligaments and tendons, due to the elastic tendencies and the fact that it is a natural product that will synthesize well with the body, and it could be used for eye sutures and jaw repairs.