Live Lobster Fects
The largest phylum of creatures on Earth without a doubt is Arthropod, both in terms of number of species and in total number of individuals. There are nearly 1 million species of Arthropods, with over 90% of them being insects. Of the remaining less than 10%, or about 85,000 species, there are only three major marine groups. The most well known is that of the mostly marine sub-phylum Crustacean (>30,000 species), the entirely marine class Pycnogonida, also called the "sea spiders" (500 species) and the entirely marine class Merostomata, commonly called the horseshoe crabs (5 species).
All Arthropods share certain characteristics making them unique from other phyla. Most obvious is the external skeleton (technically, not really a shell). Not only does this exoskeleton protect the animal like a suit of Armour, but it actually does serve as the animal's skeleton. The muscles of an Arthropod are connected to the inside of the exoskeleton, because the animal lacks an internal skeleton of any type.
The exoskeleton is made of a tough substance called chitin (KIE-tin). The animal secretes this hard material from cells in the underlying epidermis. Because the exoskeleton cannot grow, the animal must periodically shed its Armour in order to grow. This process is called molting. The animal must first grow a soft exoskeleton underneath the principal exoskeleton. Then, the animal grows enough within the principal exoskeleton to crack it. The animal then crawls out of its old exoskeleton and allows the new soft one to grow and harden. New exoskeletons are usually too large for the animal at the time of the molt, and the animal must grow into the new exoskeleton. This allows reasonable time between molts. Immediately after an Arthropod has molted, it is quite vulnerable because it is essentially defenceless. During this period, the animal will hide and wait for its Armour to harden. Lobsters caught during this period of time are sometimes called "soft-shelled" because they feel noticeably soft.
The largest phylum of creatures on Earth without a doubt is Arthropod, both in terms of number of species and in total number of individuals. There are nearly 1 million species of Arthropods, with over 90% of them being insects. Of the remaining less than 10%, or about 85,000 species, there are only three major marine groups. The most well known is that of the mostly marine sub-phylum Crustacean (>30,000 species), the entirely marine class Pycnogonida, also called the "sea spiders" (500 species) and the entirely marine class Merostomata, commonly called the horseshoe crabs (5 species).
All Arthropods share certain characteristics making them unique from other phyla. Most obvious is the external skeleton (technically, not really a shell). Not only does this exoskeleton protect the animal like a suit of Armour, but it actually does serve as the animal's skeleton. The muscles of an Arthropod are connected to the inside of the exoskeleton, because the animal lacks an internal skeleton of any type.
The exoskeleton is made of a tough substance called chitin (KIE-tin). The animal secretes this hard material from cells in the underlying epidermis. Because the exoskeleton cannot grow, the animal must periodically shed its Armour in order to grow. This process is called molting. The animal must first grow a soft exoskeleton underneath the principal exoskeleton. Then, the animal grows enough within the principal exoskeleton to crack it. The animal then crawls out of its old exoskeleton and allows the new soft one to grow and harden. New exoskeletons are usually too large for the animal at the time of the molt, and the animal must grow into the new exoskeleton. This allows reasonable time between molts. Immediately after an Arthropod has molted, it is quite vulnerable because it is essentially defenceless. During this period, the animal will hide and wait for its Armour to harden. Lobsters caught during this period of time are sometimes called "soft-shelled" because they feel noticeably soft.
Live Lobster
Live Lobster
Live Lobster
Live Lobster
Live Lobster
Live Lobster
Live Lobster
Live Lobster
Live Lobster
Live Lobster
Live Lobster
Live Lobster
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