Most scientists believe that sharks came into existence around 400 million years ago. That's 200 million years before the dinosaurs! Find out more about the history of sharks...

ARE SLOW GROWING & LATE TO MATURE - as an extreme case the Greenland Shark can live ~400 years and doesn’t reach sexual maturity until ~150 years! Many are killed before they’ve produced offspring. Besides being fun to say, ovoviviparous sharks have eggs that hatch inside of the womb and the shark has a live birth. This might sound just like the viviparous pups above, but there is no placenta involved. Pups live on a yolk sac until they are ready to hatch. The first shark to hatch from its egg will then consume the other shark fetuses and their yolk sacs. Obviously, ovoviviparous give birth to small litters. For many, the Natural History Museum is a place that inspires learning, gives purpose and provides hope. People tell us they 'still get shivers walking through the front door', and thank us for inspiring the next generation of scientists. To reverse the damage we've done and protect the future, we need the knowledge that comes from scientific discovery. Understanding and protecting life on our planet is the greatest scientific challenge of our age. And you can help. In my opinion, this was one of the best, most direct and novel hands-on approaches to shark conservation I had come across. Not only did it result in a positive outcome from the result of direct action but the potential for public engagement for this type of project was huge. Sharks are particularly vulnerable to the threats posed by humans because they reproduce slowly. They:

OVOVIVIPARITY

All shark releases so far have been public events, with the public and various dive clubs and organisations coming along to wave the sharks off. Dive clubs have even supported the releases by providing equipment such as air tanks for the divers involved. The shark pups can be viewed for a short period of time before they are taken down to depths of around 20 metres in a suitable habitat and released by the volunteer divers.

Tonic immobility is a reflex that causes a temporary state of inactivity in an animal. Similar to hypnosis. It occurs in a variety of different species, including many sharks and rays... Q: Is it feasible to keep any species of shark in a home marine tank? I’d love to hatch a shark egg out and rear the youngster. I have space for a tank of approximately 3x1.5m in my garage, with room for a sump underneath.

WHY ARE SHARKS UNDER THREAT?

A: Jeremy says: The eggs of the Brown-banded bamboo shark, Chiloscyllium punctatum, are available from specialist marine wholesalers and they will hatch in your tank, but the baby sharks hardly (if ever) feed, so if you hatch one and it dies, that’s one less shark in the oceans. If it lives and you manage to rear it successfully, they look and behave a lot like our native Dogfish, growing to a metre in length, with very flexible, very bendy bodies, and are bottom-dwelling. O’Bryhim, JR, Parsons, ECM, 2015. Increased knowledge about sharks increases public concern about their conservation. Marine Policy 56, 43–47. PRODUCE FEW YOUNG - varying from 2 pups for the Bigeye Thresher and up to 135 for the Blue Shark. Compare this to the reproduction potential of bony-fish who release millions of eggs.

This project by Sharklab-Malta is one that can be adopted and adapted for oviparous elasmobranch species worldwide. For example, I have successfully replicated this with S. canicula landed in the North Sea. It is without a doubt valuable for future conservation efforts. References Viviparity is the most advanced method of reproduction. The baby shark develops inside their mother’s body, receiving nutrients and oxygen through an umbilical cord. This is the same method used by mammals. But, unlike mammals, when the pups are born they're immediately independent and have to fend for themselves.The protective capsule acts as a life-support machine, containing everything that's needed. The embryo absorbs nutrients from a yolk-sac before hatching. And emerges as a miniature version of the adult. Every year, more people are reading our articles to learn about the challenges facing the natural world. Our future depends on nature, but we are not doing enough to protect our life support system. Pollution has caused toxic air in our cities, and farming and logging have wreaked havoc on our forests. Climate change is creating deserts and dead zones, and hunting is driving many species to the brink of extinction. This is the first time in Earth's history that a single species - humanity - has brought such disaster upon the natural world. But if we don't look after nature, nature can't look after us. We must act on scientific evidence, we must act together, and we must act now. Many shark species have brains as complex as mammals, which enables them to process a wide range of senses. Sharks have the same 5 senses as we do plus a couple more... Today, many aquariums and research facilities use Dr. Clark’s target training and feeding method to attract sharks to a designated feeding area. The feeding method is a helpful way to ensure each shark gets the right amount and type of food, which is especially important when feeding a mix of shark species in one pool. Oviparity is when eggs are fertilized in the womb and then a shark lays the eggs encased in a leathery pouch, called a “mermaid’s purse.” The eggs are left unprotected and are oftentimes eaten by predators before they can hatch. The eggs hatch with no parental care after the eggs are laid.

Skate, chimaera and some shark species produce eggs encased in a tough 'leathery' eggcase. A female may spend a long time laying her eggs, ensuring they’re securely fixed in a safe place. It can take between 6-9 months before they’re ready to hatch.

Senses and Sensibilities

In the 1950s, "Shark Lady” and ocean science pioneer, Dr. Eugenie Clark, discovered that sharks can recognize colors, shapes, learn to perform behaviors. By teaching lemon sharks that pressing an underwater target would earn food rewards, Clark demonstrated that sharks can be trained. Whether you’ve submitted one eggcase or thousands, every eggcase adds to the Great Eggcase Hunt database and helps us to gain a better understanding of egg-laying sharks, skates and chimaera. Adopt a Great White Shark today and you'll be supporting vital Great White Shark research in the USA. Tens of millions of sharks are killed each year and many populations continue to decline at an alarming rate.