New World Spider vs. Old World Spider

Attribute	New World Spider	Old World Spider
Location	Americas, Australia, and Pacific Islands	Africa, Asia, Europe, and Australia
Fangs	Shorter fangs that strike downwards	Longer fangs that strike sideways
Webs	Typically build tangled webs	Typically build orb-shaped webs
Behavior	More likely to be aggressive	More likely to be defensive

Physical Attributes

New World spiders and Old World spiders have distinct physical attributes that set them apart. New World spiders, which are primarily found in the Americas, tend to have more vibrant colors and patterns on their bodies. They also have urticating hairs on their abdomens, which they can flick at predators as a defense mechanism. In contrast, Old World spiders, found in Europe, Asia, and Africa, often have more muted colors and patterns. They do not possess urticating hairs but may have other defensive mechanisms such as venomous bites or stingers.

Habitat

The habitat preferences of New World spiders and Old World spiders also differ. New World spiders are typically found in warmer climates, such as tropical rainforests or deserts. They may build their webs in trees, bushes, or on the ground. Old World spiders, on the other hand, are more commonly found in temperate regions, such as forests or grasslands. They may build their webs in vegetation, on rocks, or even in human structures like houses or barns.

Behavior

When it comes to behavior, New World spiders and Old World spiders exhibit some interesting differences. New World spiders are known for their unique hunting techniques, such as actively stalking prey or using their webs to trap insects. Some New World spiders, like the tarantula, are also known to be more aggressive and may bite if threatened. In contrast, Old World spiders are often more passive in their hunting strategies, relying on their webs to catch prey. They may be less likely to bite humans unless provoked.

Venom

One of the most significant differences between New World spiders and Old World spiders is the composition of their venom. New World spiders, particularly those in the Theraphosidae family like tarantulas, have venom that is generally less potent to humans. Their venom is primarily used to subdue prey rather than for self-defense. Old World spiders, on the other hand, such as the black widow or brown recluse, have venom that can be more harmful to humans. Their venom is often used for both subduing prey and defending against predators.

Web Structure

The structure of the webs built by New World spiders and Old World spiders can also vary significantly. New World spiders, like orb-weavers, are known for their intricate and symmetrical webs that are designed to catch flying insects. These webs are often large and circular in shape, with radial lines extending outward from the center. Old World spiders, on the other hand, may build irregular or funnel-shaped webs that are better suited for trapping ground-dwelling insects. These webs may be smaller and less conspicuous compared to those of New World spiders.

Reproduction

Reproductive strategies differ between New World spiders and Old World spiders as well. New World spiders often engage in elaborate courtship rituals before mating, with males performing intricate dances or presenting gifts to females. Some New World spiders may also exhibit maternal care, with females guarding their egg sacs or even carrying their young on their backs. In contrast, Old World spiders typically have more straightforward mating rituals, with males simply approaching females and mating quickly. Maternal care is less common among Old World spiders, with females often laying their eggs and then abandoning them.

Conclusion

In conclusion, New World spiders and Old World spiders have several distinct attributes that differentiate them from each other. From their physical appearance and habitat preferences to their behavior and venom composition, these two groups of spiders have evolved unique adaptations to thrive in their respective environments. By understanding the differences between New World spiders and Old World spiders, we can gain a greater appreciation for the diversity and complexity of the arachnid world.